George James Robertson
A Thesis Submitted for the Degree of PhD at the
University of St Andrews
1924
Full metadata for this item is available in St Andrews Research Repository
at:
http://research-repository.st-andrews.ac.uk/
Please use this identifier to cite or link to this item: http://hdl.handle.net/10023/11229
INVESTIGATIONS ON CELLULOSE
BEING A THESIS
PRESENTED BY
GEORGE JAMES ROBERTSON,M.A.,B.SC.,
TO THE UNIVERSITY OP ST.ANDREWS
IN APPLICATION FOR THE DECREE OF PH.D.
All rights reserved
INFORMATION TO ALL USERS
The quality of this reproduction is dependent upon the quality of the copy submitted.
In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed,
a note will indicate the deletion.
uest.
ProQuest 10166114
Published by ProQuest LLC(2016). Copyright of the Dissertation is held by the Author.
All rights reserved.
This work is protected against unauthorized copying under Title 17, United States Code. Microform Edition © ProQuest LLC.
ProQuest LLC
789 East Eisenhower Parkway P.Q. Box 1346
% g
-(j ■ .
7 • I. '
.
:ÿàl
'I : t
'■ Ï ,
■Vk
^^■'1 :
UNIVERSITY CAREER AHD RRSICARCH EXPERIENCE.
I g r a d u a te d M .A .in t h e U n i v e r s i t y o f 8 t . Andrews i n
1 9 3 1 , and B * S c .,v / i t h F i r s t C l a s s Honours i n C h e m istr y ,
i n 1 9 3 2 .
I commenced t h e r e s e a r c h on E sp a r to C e l l u l o s e , which
i s no\7 h e i n c s u b m it t e d a s a P h . D , T h e s i s , i n February
1 9 2 2 , and was a d m itte d a R esearch S tu d e n t o f t h e
U n i v e r s i t y from May 1 9 2 2 .
In 1922 I was awarded a C a rn ec ie R ese a rc h S c h o l a r s h i p
which I have h e l d f o r t h e p a s t two y e a r s .
In a d d i t i o n t o t h e work which i s d e s c r i b e d i n t h i s
t h e s i s , I have b een e n c a s e d on t h e i n v e s t i g a t i o n o f
t h e o p t i c a l i n v e r s i o n o f 1-m enthone and t h e a s s o c i a t e d
problem d e a l i n g w ith t h e r e l a t i o n s h i p o f t h e v a r i o u s
m e n th o ls and m e n t h o n e s .T h is work h a s bean c a r r i e d o u t
r
( i v )C O N T E N T S .
PART ONE.
THE NATURE OF ESPARTO CELLULOSE.
I n t r o d u c t i o n ... C l ) .
The O b je c t o f t h e R e s e a r c h ... ( 1 8 ) .
The C o m p o sitio n o f E s p a r to C e l l u l o s e ...( 1 9 ) .
The Hexose R e s id u e i n E s p a r to C e l l u l o s e ...( 2 6 ) .
D i s c u s s i o n o f t h e R e s u l t s ... . ( 3 3 ) .
E x p e r i m e n t a l ( 3 6 ) t o ( 5 3 ) .
PART TWO.
THE STRUCTURAL BASIS OF COTTON CELLULOSE.
I n t r o d u c t i o n ... ...(54 ) .
The O b je c t o f t h e R e s e a r c h ...( 5 7 ) .
O u t l i n e o f t h e Work... ( 5 8 ) .
D i s c u s s i o n o f t h e R e s u l t s ... ( 6 5 ) .
PART ONE,
THEORETICAL.
Tîie name ’’c e l l u l o s e * * i s a g e n e r i c term a p p l i e d t o a
c l a s s o f s u b s t a n c e s r a t h e r th a n t o an i n d i v i d u a l
s p e c i f i c a l l y c h a r a c t e r i s e d by i t s p h y s i c a l and c h e m ic a l
p r o p e r t i e s , a n d , a s m ight be e x p e c t e d from t h e f a c t
t h a t c e l l u l o s e form s t h e p r e d o m in a t in g c o n s t i t u e n t
o f p l a n t t i s s u e s , t h e r e e x i s t s a wide ran ge o f d i v e r g e n t
m o d i f i c a t i o n s , i n c o n f o r m it y w ith t h e v a r i e t y o f
n a t u r a l e l a b o r a t i o n . A s a c l a s s , t h e c e l l u l o s e s have
many p r o p e r t i e s i n common.They are c h e m i c a l l y i n e r t ,
c o l o u r l e s s and o d o u r l e s s b o d i e s ,w h i c h are r e p r e s e n t e d
e m p i r i c a l l y by t h e fo r m u la (C^H,^0^^,in w hich ’*n** i s
an i n t e g e r o f unknovm m agnitu de .They a re f a r t h e r
c h a r a c t e r i s e d by t h e i r i n s o l u b i l i t y i n s im p le o r g a n i c
s o l v e n t s and by t h e i r r e s i s t a n c e , a lt h o u g h i n v a r y i n g
d e g r e e , t o t h e p r o c e s s e s o f h y d r o l y s i s and o x i d a t i o n .
I t s h o u ld be n o t e d t h a t t h e c e l l u l o s e s are
n o t r e a d i l y s e p a r a t e d from t h e p l a n t i n a s t a t e o f
" p u r i t y " ,b u t a re u s u a l l y a s s o c i a t e d vd.th s m a ll amounts
o f f o r e i g n m a t e r i a l , which may be i n t i m a t e l y mixed
( 2 )
Such i m p u r i t i e s are g e n e r a l l y l e s s r e s i s t a n t t o
h y d r o l y s i s and o x i d a t i o n and may he e l i m i n a t e d hy
t h e a c t i o n o f a l k a l i n e h y d r o x id e s under p r e s s u r e ,
f o l l o w e d hy e x p o s u r e t o t h e a c t i o n o f c l l o r i n e r;as
a t t h e o r d in a r y t e m p e r a tu r e .The r e s i d u e vdiich r e s u l t s
from t h i s t r e a t m e n t , a f t e r th o r o u g h w ash ing and d r y i n g ,
i s r e g a r d e d a s a b n o r m a l " c e l l u l o s e .
A cco rd in g t o C ross and B evan, ( ’’C e l l u l o s e ",
Second E d i t i o n , 1910 ,P . 7 8 ) , ’’t h e c e l l u l o s e s o f t h e
p l a n t w orld so f a r a s t h e y have h e e n i n v e s t i g a t e d
from t h e p o i n t o f v ie w o f c h e m ic a l c o n s t i t u t i o n ,
group t h e m s e l v e s a s f o l l o w s
( a ) Those o f maximum r e s i s t a n c e t o h y d r o l y t i c a c t i o n ,
and c o n t a i n i n g no d i r e c t l y a c t i v e CO g r o u p s ,
( h ) Those o f l e s s e r r e s i s t a n c e t o h y d r o l y t i c a c t i o n ,
j and c o n t a i n i n g a c t i v e CO g r o u p s ,
( c ) Those o f lo w r e s i s t a m c e t o h y d r o l y s i s , i . e . m o r e
o r l e s s s o l u b l e i n a l k a l i n e s o l u t i o n s and e a s i l y
r e s o l v e d hy a c i d s , w i t h f o r m a t io n o f c a r b o h y d r a t e s o f
low m o le c u la r w e ig h t V
In an e x p a n s io n o f t h e above c l a s s i f i c a t i o n
t h e same a u t h o r s p l a c e t h e t y p i c a l c o t t o n c e l l u l o s e
1 a lo n g w ith t h e c e l l u l o s e s o f F l a x , Hemp, China G rass
and Sunn Hemp i n group ( a ) , a n d t h e c e l l u l o s e s o b t a i n e d
from w o o d ; c e r e a l s t r a w s and e s p a r t o g r a s s i n group ( b ) .
M oreover, t h e y re g a rd t h e c e l l u l o s e s d e r i v e d from
c e r e a l s t r a w s and e s p a r t o g r a s s a s b e i n g s t r o n g l y
d i f f e r e n t i a t e d from t h e normal and c h a r a c t e r i s e them
a s p ron oun ced o x y c e l l u l e s e s . T h i s v i e w ,w i t h r e g a r d t o
e s p a r t o c e l l u l o s e , w i l l be r e f e r r e d t o a t a l a t e r
s ta g e .G r o u p ( c ) i s o f l i t t l e i n t e r e s t i n r e l a t i o n
t o t h e p r e s e n t t h e s i s , a s i t i n c l u d e s t h e h e t e r o g e n e o u s
c l a s s o f c e l l u l a r a s op p osed t o f i b r o u s c e l l u l o s e s ,
f o r which E .S c h u lz e h a s p ro p o se d t h e term P seu d o
c e l l u l o s e s , and may be d i s m i s s e d w it h o u t f a r t h e r r e f e r e n c e .
THE CONSTITUTION OF COTTON CELLULOSE.
« The a t t e n t i o n o f i n v e s t i g a t o r s was n a t u r a l l y f i r s t
a t t r a c t e d t o t h e c o n s t i t u t i o n a l s tu d y o f c o t t o n
c e l l u l o s e , which may be r e f e r r e d t o a s t h e t y p i c a l
c e l l u l o s e , b u t many s e r i o u s , a l m o s t i n s u p e r a b l e
d i f f i c u l t i e s l a y i n t h e p a th o f t h e p i o n e e r s who
a t t a c k e d t h i s i n t r i c a t e problem o f c a r b o h y d r a te c h e m i s t r y .
The v e r y n a tu r e o f c e l l u l o s e , i t s i n s o l u b i l i t y i n
s im p le o r g a n i c s o l v e n t s , i t s u n c e r t a i n , o r r a t h e r unknown
( 4 )
f i b r o u s m a t e r i a l i t n i g h t be h e t e r o g e n e o u s , vfere
f a c t o r s which c a l l e d f o r no n e an pow ers o f i n g e n u i t y
and r e s o u r c e i n t h e i r e l u c i d a t i o n , I n a d d i t i o n t o t h i s ^
t h e e a r l y i n v e s t i g a t o r s were hampered by an in a d e q u a t e
know ledge o f t h e s i m p l e r c a r b o h y d r a t e s ,a know ledge
which h a s s u b s e q u e n t l y p roved i n v a l u a b l e i n c o n s t i t u t i o n a l
s t u d i e s o f t h i s t y p e , I n t h e f a c e o f such d i f f i c u l t i e s
t h e e a r l y c o n t r i b u t i o n s t o th e s u b j e c t are by no
means i n s i g n i f i c a n t , b u t i t i s n o t s u r p r i s i n g t h a t a
v i o l e n t c o n f l i c t o f o p i n i o n a r o s e , w i t h t h e r e s u l t
t h a t p r o g r e s s was impeded f o r many y e a r s .
The l i t e r a t u r e on t h e c o n s t i t u t i o n o f c e l l u l o s e
i s e x c e e d i n g l y e x t e n s i v e , b ut t h e r e s u l t s which were
o b t a i n e d i n e a r l y i n v e s t i g a t i o n s and t h e i l l o g i c a l
s p e c u l a t i o n s which were b a sed upon them are so c o n f u s i n g
a s t o r e n d e r a summary u n d e s i r a b l e and e v e n u n n e c e s s a r y .
In t h e l i g h t o f r e c e n t r e s e a r c h e s c a r r i e d o u t i n
t h i s l a b o r a t o r y by J .C * I r v i n e and h i s c o l l a b o r a t o r s ,
i t seem s more a p p r o p r i a t e , a s a p r e f a c e t o t h i s e s s a y ,
t o o u t l i n e t h e v a r i o u s s t e p s by which t h e p r e s e n t
c o n c e p t i o n o f c e l l u l o s e s t r u c t u r e was a r r i v e d a t ,
The argument i s b ased on two w e ll-k n o w n and
" ( 1 ) C e l l u l o s e , (C^ H , on c o m p le te hydro l y s i s , i s
c o n v e r t e d q u a n t i t a t i v e l y i n t o g l u c o s e .
( 2 ) The graded h y d r o l y s i s und ergone hy c e l l u l o s e
d u r in g a c e t o l y s i s may he a r r e s t e d a t a s t a g e where
t h e d i s a c c h a r i d e c e l l o h i o s e i s a d e f i n i t e p r o d u c t ’,’
( I r v i n e and H i r s t , T . , 1 9 2 3 , 1 2 3 , 5 1 8 )
I t h a s l o n g h e e n m a in t a in e d t h a t t h e u l t i m a t e h y d r o l y s i s
o f c o t t o n c e l l u l o s e hy means o f m in e r a l a c i d s p r o c e e d s
q u a n t i t a t i v e l y i n a cc o rd a n c e w ith t h e e q u a t io n
hut u n t i l r e c e n t l y , t h e e v i d e n c e adduced i n su p p o rt
o f t h e v ie w t h a t t h e p r o d u c t c o n s i s t e d e n t i r e l y o f
g l u c o s e was hy no means c o n c l u s i v e .
The v a l i d i t y o f h y d r o l y t i c c l e a v a g e a s a
means t o a s c e r t a i n i n g s t r u c t u r e may on f i r s t
c o n s i d e r a t i o n s he q u e s t i o n e d , i n v ie w o f t h e d i s c o v e r y
o f a t h i r d t y p e o f m e t h y l g l u c o s i d e which was o b t a in e d
as an u n c r y s t a l l i s a h l e s y r u p , i n a d d i t i o n t o t h e
c r y s t a l l i n e o ( a n d / 3 m e t h y l g l u c o s i d e s , h y t h e a c t i o n o f
m ethyl a l c o h o l c o n t a i n i n g 1 p e r c e n t o f h ydrogen
c h l o r i d e on g l u c o s e . (S m il F i s c h e r , B e r . , 1 9 1 4 , 4 7 , 1 9 8 6 0
In t h e f o l l o w i n g y e a r , I r v i n e , P y f e and H ogg, ( T . ,1 9 1 5
(G)
o f i s o m e r i d e s d e r i v e d from an e n t i r e l y new v a r i e t y
o f G l u c o s e , t o w hich t h e y a s c r i b e d an e t h y l e n e o x id e
s t r u c t u r e . O t h e r h e x o s e d e r i v a t i v e s , which shew t h e
same c h a r a c t e r i s t i c s , h a v e s u b s e q u e n t ly b een i s o l a t e d .
The a d d i t i o n a l c o m l p i c a t i o n which t h i s
d i s c o v e r y b r i n g s i n t o c o n s t i t u t i o n a l c o n s i d e r a t i o n s ,
and t h e i n c r e a s e d c a u t i o n which must be e x e r c i s e d
i n t h e i n t e r p r e t a t i o n o f r e s u l t s from h y d r o l y s i s ,
are s e l f - e v i d e n t , A n o t a b l e c a s e i s found i n i n u l i n ,
Wlien i n u l i n i s h y d r o ly s e d e i t h e r by d i l u t e h y d r o c h l o r i c
a c i d o r by o x a l i c a c i d , o r d i n a r y l a e v o - r o t a t o r y f r u c t o s e
r e s u l t s . VThen, h o w e v e r , i n u l i n i s f i r s t m e t h y la t e d and
t h e r e s u l t i n g t r i m e t h y l i n u l i n i s h y d r o l y s e d , a d e x t r o
r o t a t o r y t r i m e t h y l f r u c t o s e r e s u l t s . ( I r v i n e and S t e e l e ,
T . , 1 9 2 0 , 1 1 7 , 1 4 7 4 )The n e c e s s a r y i n f e r e n c e i s t h a t
f r u c t o s e e x i s t s i n i n u l i n presum ably a s an am ylene
o x id e t y p e ,w h i c h i s c o n v e r te d i n t o t h e u s u a l b u t y le n e
o x id e v a r i e t y on h y d r o l y s i s , u n l e s s such change i s
p r e c lu d e d by m e t h y l a t i o n . l t i s c l e a r , h o w e v e r , t h a t i n
d e t e r m in in g t h e q u a n t i t a t i v e n a tu r e o f t h e c o n v e r s i o n
o f c e l l u l o s e t o g l u c o s e ,t h e v a l i d i t y o f h y d r o l y s i s i s
u n im p a ire d .T h e i n t e r n a l s t r u c t u r e o f t h e r e s u l t i n g
i d e n t i t y and aiBonnt o f t h e s u r a r are i n no w is e a f f e c t e d .
Many i n v e s t i g a t o r s have c o n f i d e n t l y c l a i a e d
q u a n t i t a t i v e y i e l d s o f g l u c o s e froD c e l l u l o s e hy
h y d r o l y s i s . P l e c h s i g , ( Z e i t s c h . p h s i o l . Cheu. , 1 8 8 3 , 7 , 5 2 3 ) ,
u s i n g c o n c e n t r a t e d s u l p h u r i c a c i d a s t h e h y d r o l y t i c
a g e n t j C la iD e d t o have o b t a i n e d a y i e l d o f g l u c o s e
c o r r e s p o n d in g w ith 9 5 - 9 8 p e r c e n t o f t h e t h e o r e t i c a l
q u a n t i t y a v a i l a b l e f r o a c e l l u l o s e , a c l a i a , m o r e o v e r ,
which he b ased e n t i r e l y on t h e cop p er r e d u c i n g power
o f t h e s o l u t i o n o b t a i n e d .
Working on s i a i l a r l i n e s , O s t and W ilken i n g ,
( C h e a . Z e i t , , 1 9 1 0 , 3 4 , 4 6 1 ) , c l a i a e d a l a o s t q u a n t i t a t i v e
y i e l d s o f g l u c o s e by t h e a c t i o n o f 7 2 p e r c e n t s u l p h u r i c
a c i d on c e l l u l o s e . I n t h i s c a s e t h e c l a i a was b ased
on p o l a r i a e t r i c r e a d in g s .N o w i t i s s u r e l y c l e a r , t h a t
w h i l e t h e above m ethods o f e s t i m a t i o n may a f f o r d
v a l u a b l e c o n f ir m a t o r y e v i d e n c e , t h e y can s c a r c e l y be
a llo w e d a s fu n d a m en ta l p r o o f .
A few y e a r s l a t e r , W i l l s t a t t e r and Z e c h m e is t e r ,
(H er. , 1 9 1 3 , 4 6 , 2 4 0 1 ) , i n v e s t i g a t e d t h e h y d r o l y s i s o f
c o t t o n wool w it h 4 0 - 4 1 p e r c e n t h y d r o c h l o r i c a c i d .
They u s e d a 1 p e r c e n t s o l u t i o n o f c e l l u l o s e and
( 8 )
The y i e l d o f [glu cose t h u s i n d i c a t e d v/as e ( s u iv a ie n t
t o 96 p e r c e n t o f t h e t h e o r e t i c a l q u a n t i t y , a n d t h i s
was a p p a r e n t ly c o n fir m e d by copper r e d u c t i o n f i r u r e s .
The u se o f c o n c e n t r a t e d h y d r o c h l o r i c a c i d i s , h o w e v e r ,
open t o e v e n s t r o n g e r o b j e c t i o n s t h a n t h e u s e o f
c o n c e n t r a t e d s u l p h u r i c a c i d . F i s c h e r , ( B a r , , 1 8 9 0 , 2 3 , 3 6 8 7 ;
1 0 9 5 , 2 8 , 3 0 2 4 ) , had p r e v i o u s l y she\m t h a t i n t h e p r e s e n c e
o f c o n c e n t r a t e d h y d r o c h l o r i c a c i d g l u c o s e u n d e r g o e s
c o n d e n s a t io n t o foria i s o - D a l t o s e ,b u t V f i l l s t a t t e r and
Z e c h m e iste r were o f t h e o p i n i o n t h a t no i s o - m a l t o s e
was formed d u r in g t h e i r * h y d r o l y s i s ow ing t o t h e lo w
c o n c e n t r a t i o n o f g l u c o s e p r e s e n t . T h i s p o i n t h a s s i n c e
b een r e f u t e d by D a v i s , ( J . S e e . D y e r s and C o l l . , 1 9 1 4 , 3 0 , 2 4 9 ) ,
who proved t h a t t h e a c t i o n o f h y d r o c h l o r i c a c i d i n
e f f e c t i n g t h e a u t o - c o n d e n s a t i o n o f g l u c o s e e x t e n d s
t o s o l u t i o n s c o n t a i n i n g o n l y 1 p e r c e n t o f g l u c o s e .
R e a l i s i n g t h e u n s a t i s f a c t o r y n a tu r e o f such
i n v e s t i g a t i o n s , I r v i n e and S o u t a r , ( T . , 1 9 2 0 , 1 1 7 , 1 4 8 9 ) ,
a t t a c k e d t h e problem from a n o th e r a n g l e . C o t t o n c e l l u l o s e
was f i r s t t r a n s fo r m e d i n t o t h e c o r r e s p o n d in g t r i a c e t a t e
by means o f grad ed a c e t o l y s i s w ith a m ix tu r e o f a c e t i c
anhydride and s u l p h u r i c a c id .T h e t r i a c e t a t e was t h e n
h y d r o l y s i s and c o n d e n s a t i o n vrith a c i d m eth y l a l c o h o l ,
and f i n a l l y i n t o t h e p a r e n t h e x o s e .T h e y i e l d o f c l n c o s e
t h u s o b t a i n e d wa,s 85 p e r c e n t o f t h e t h e o r e t i c a l
amount o b t a i n a b l e from c e l l u l o s e , c a l c u l a t e d on t h e
a ssu m p tio n t h a t c e l l u l o s e i s e n t i r e l y composed o f
h e x o se r e s i d u e s . I n t h e above p r e p a r a t i o n o f c e l l u l o s e
t r i a c e t a t e , a c o n s i d e r a b l e q u a n t i t y o f s o l u b l e m a t e r i a l
rem ained i n t h e aq u eou s l i q u o r s a f t e r p r e c i p i t a t i o n
o f t h e a c e t a t e , t h e i s o l a t i o n o f which i n v o l v e d a
tr o u b le s o m e s e r i e s o f o p e r a t i o n s a s w e l l a s u n a v o id a b le
l o s s . A f a r t h e r r e s e a r c h on t h e s u b j e c t was t h e r e f o r e
und ertciken, ( I r v i n e and H i r s t , T . , 1 0 2 2 , l 3 1 , 1 5 8 5 ) , v r i t h a
v ie w t o a c c o u n t i n g f o r t h i s d i v e r g e n c e o f 15 p e r c e n t
from t h e t h e o r e t i c a l v a l u e .
An im proved method o f a c e t o l y s i s a s d e s c r i b e d
by V/.L• B a r n e t t , ( J . S o c . C h e m . I n d . , 1 9 2 1 , 4 0 ,8 T ) ,v^as made
u se o f , a n d an e x c e l l e n t y i e l d o f u n ifo rm t r i a c e t a t e
was o b t a in e d .N o d i s s o l v e d su gar was found i n t h e aqueous
w a sh in g s and t h e o p e r a t i o n s r e f e r r e d t o above were
t h u s e l i m i n a t e d .O n s u b m i t t i n g t h e t r i a c e t a t e t o
t r e a t m e n t w ith m e th y l a l c o h o l c o n t a i n i n g 1 p e r c e n t
o f hydrogen c h l o r i d e i n s e a l e d t u b e s , a y i e l d o f
( 1 0 )
c e n t o f t h e t h e o r e t i c a l ojiio-ant.Evidence was a l s o
o b t a in e d t h a t t h e w hole o f t h e m a t e r i a l i s o l a t e d v/as
composed o f m e t h y l c l n c o s i d e w it h o u t ad m ixtu re vdLth
d e r i v a t i v e s o f o t h e r h e x o s e s o r o f p e n t o s e s . l t ca n n o t
be em p h a sised t o o s t r o n g l y t h a t t h e above c l a i m s are
b ased upon t h e a c t u a l amount o f a n a l y t i c a l l y pure
m a t e r i a l i s o l a t e d , a n d so f o r t h e f i r s t tim e t h e
q u a n t i t a t i v e c o n v e r s i o n o f c o t t o n c e l l u l o s e t o g l u c o s e
was f i r m l y e s t a b l i s h e d .
Beyond t h e f a c t t h a t t h e c o t t o n c e l l u l o s e
m o le c u le i s composed o f {glucose r e s i d u e s , t h e e v i d e n c e
d e s c r i b e d above r i v e s no c l u e t o t h e m o le c u la r s t r u c t u r e .
No i n d i c a t i o n i s ^ iv e n o f t h e h y d r o x y l c r o u p s which .
are i n v o l v e d i n t h e l i n k a r e o f t h e g l u c o s e r e s id u e s ^
and no i n f e r e n c e ca.n be dravm a s t o t h e i n t e r n a l
s t r u c t u r e o f each component g l u c o s e r e s i d u e . T h i s
i n f o r m a t i o n v/as s u p p l i e d by t h e m é t h y l a t i o n o f c e l l u l o s e
and t h e s^absequent h y d r o l y s i s o f t h e a l k y l a t e d p r o d u c t ,
v/hich v/as f i r s t u n d e r ta k e n by Denham and Woodliouse.
(T . , 1 9 1 5 , 1 0 3 , 1 7 3 5 ) . A m eth ylated , c e l l u l o s e c o n t a i n i n g
25 p e r c e n t o f m eth o x y l was o b t a in e d ,v /h ic h on h y d r o l y s i s
y i e l d e d among o t h e r p r o d u c t s a c r y s t a l l i n e t r i m e t h y l
CH.OH ___
CH.OCHy. . .
CH . 0 . . . --- 3
CH.OH ___
CI^OCH). . . .
T h is c o n s t i t u t i o n was confirmed, by I r v i n e and H i r s t .
( T . , 1 9 2 2 , 1 2 1 , 1 2 1 3 )
Proa t h i s i t f o l l o w s t h a t c e l l u l o s e i s a
d e r i v a t i v e o f {glucose i n which t h e p o s i t i o n s 1 and 5
are r e p l a c e d by one o r a o r e a n h y d r o ^ lu c o se r e s i d u e s ,
s i n c e t h e s e p o s i t i o n s are o b v i o u s l y p r o t e c t e d f r o a
a e t h y l a t i o n . l t was c l e a r l y d e s i r a b l e t o a e t h y l a t e
c o t t o n c e l l u l o s e t o t h e a a x ia u a e x t e n t , a n d a t t h e
r e q u e s t o f Dr. D e n h a a ,th e t a s k was und ertalcen by I r v i n e
and H i D s t . ( T , , 1 9 2 3 , 1 2 3 , 5 1 8 ) .As was t o be e x p e c t e d t h e
p r o d u c t o f a a x ia u a a e t h y l a t i o n c o r r e sp o n d e d w it h a
t r i a e t h y l c e l l u l o s e , and a l l e f f o r t s t o i n c r e a s e t h e
a e t h o x y l c o n t e n t f a r t h e r were u n s u c c e s s f u l . O n h y d r o l y s i n g
t h e a l k y l a t e d p r o d u c t t h e siij^ p lest o f a l l p o s s i b l e
r e s u l t s was o b t a i n e d , a s no su g a r o t h e r th a n 2 : 3 : 6
-t r i a e -t h y l g l u c ô s e was i s o l a -t e d . T h e c e l l u l o s e a o l e c u l e
( 1 2 )
r e s i d u e s which are l i n k e d th r o u g h t h e p o s i t i o n s 1
and 5 .
The r e m a in in g p o i n t t o be c o n s i d e r e d i s t h e
f o r m a t io n o f c e l l o b i o s e o c j î a c e t a t e by t h e graded
a c e t o l y s i s o f c o t t o n c e l l u l o s e . T h e l i n k a g e i n
c e l l o b i o s e i s one which o c c u r s o n l y i n n a t u r a l
c a r b o h y d r a t e s ,a n d t h i s f a c t , i n c o n j u n c t i o n vrLth t h e
e v i d e n c e t h a t c e l l o b i o s e , on m é t h y l a t i o n and s u b s e q u e n t
h y d r o l y s i s , y i e l d s 2 : 3 : 6 - t r i m e t h y l g l u c o s e , (Hav/orth
and H i r s t , T . , 1 9 2 1 , 1 1 9 , 1 9 3 ) , p o i n t s t o t h e i d e a t h a t
c e l l o b i o s e form s p o r t o f t h e c e l l u l o s e m o l e c u l e , a s
e x p e r im e n t a l e v i d e n c e i s e n t i r e l y o p p o sed t o t h e v ie w
t h a t c e l l o b i o s e may be form ed d u r in g a c e t o l y s i s by
t h e a u t o - c o n d e n s a t i o n o f g l u c o s e , I f t h e c e l l u l o s e
m o le c u le c o n s i s t s o f two a n h y d r o g lu c o s e r e s i d u e s
l i n k e d th r o u g h p o s i t i o n s 1 and 5 ,1 0 0 p a r t s o f c e l l u l o s e
s h o u ld y i e l d 105 p a r t s o f c e l l o b i o s e , b u t t h e h i g h e s t
r e c o r d e d y i e l d s o f t h e d i s a c c h a r i d e a re o f t h e o r d e r
o f 50 t o 60 p e r c e n t .T h e f o l l o w i n g m o l e c u l a r s t r u c t u r e ,
which s a t i s f i e s a l l t h e r e q u ir e m e n t s o u t l i n e d a b o v e,
and would g i v e y i e l d s o f c e l l o b i o s e a p p r o x im a tin g
t o t h e lo w e r f i g u r e s q u o te d a b o v e ,h a s b een s u g g e s t e d
n n— (
H.on
& .0 H
-CH
RpOH
.—°—
1
[I C H . C H ( Ô H ) . C H ( O H ) . Ç I Î
.OH
Ô
H . C H ( O H ) . C H ( O H ) . ( j ; i I . C H . C I ^ O H
—0---I t s h o u ld he p o i n t e d o u t t h a t t h e t h r e e a n h y d r o g lu c o s e
r e s i d u e s i n t h e above fo r m u la Day he a r r a n r e d i n
o t h e r ways and s t i l l f u l f i l a l l t h e r e q u i r e m e n t s ,h u t
a s such a r e a r r a n c e m e n t would e n t a i l t h e p o s s i b i l i t y
o f c e l l u l o s e y i e l d i n g d i s a c c h a r i d e s o t h e r t h a n c e l l o h i o s e ,
t h e ahove i s a t p r e s e n t p r e f e r r e d a s t h e s i m p l e s t
r e p r e s e n t a t i o n o f a m o l e c u l e , w h ic h , p o ly m e r is e d i n
unknown num bers,w ou ld r e p r e s e n t c o t t o n c e l l u l o s e a s
( 1 4 )
TH^ ULTIMATE HYDROLYSIS OF ESPARTO CSLLULOSIi:.
Aa a p a r t o f t h e e x p e r i m e n t a l programme o f t h i s
l a b o r a t o r y , a r e s e a r c h , p a r a l l e l w ith t h a t a lr e a d y
d e s c r i b e d i n t h e c a s e o f c o t t o n c e l l u l o s e , was commenced
o n " e s p a r to c e l l u l o s e *'a term which i s a p p l i e d t o t h e
p r o d u c t w hich i s o b t a i n e d from e s p a r t o [ ir a s s by
y h e a t i n r u n d er p r e s s u r e w it h a l k a l i and t h e r e a f t e r *
\ rem ovin g l i ^ n i n and c o l o u r i n g m a t t e r by t r e a t m e n t
w it h c h l o r i n e .E s p a r t o c e l l u l o s e i s a f i b r o u s m a t e r i a l
yvo s ^ e w h a t s i m i l a r t o c o t t o n c e l l u l o s e i n appeoT ance,
b ut i t d i f f e r s m arkedly i n t h a t i t c i v e s a y i e l d o f
f u r f u r a l , c o r r e s p o n d in g w ith IB t o 20 p e r c e n t o f
p e n t o s a n , o n d i s t i l l a t i o n w ith 12 p e r c e n t h y d r o c h l o r i c
a c i d .T h e f o l l o w i n g i n v e s t i g a t i o n , v / h i c h i n v o l v e d t h e
i d e n t i f i c a t i o n o f t h e p e n t o s e p r e s e n t i n e s p a r t o
c e l l u l o s e , a lo n g v /ith t h e a c é t y l a t i o n o f t h e c e l l u l o s e
and t h e s u b s e q u e n t h y d r o l y s i s o f t h e a c e t a t e , w a s
c a r r i e d o u t by I r v i n e and H i r s t . (T , , 1 9 2 4 , 1 2 5 , 1 5 ) .
A number o f p e n t o s e e s t i m a t i o n s v/ere c a r r i e d
o u t on e s p a r t o c e l l u l o s e and t h e v a r i o u s r e s u l t s
v/hich were o b t e l n e d l a y betv/een t h e l i m i t s o f 18 and
20 p e r c e n t o f p e n t o s a n . I n t h e c o u r s e o f s u b s e q u e n t
o f t h e c e l l u l o s e w ith " b o ilin g sodiuio h y d r o x id e r e s u l t e d
i n s o l u t i o n o f t h e p e n t o s a n c o n s t i t u e n t . I t i s p r o b a b l e ,
t h e r e f o r e , t h a t t h e p r e liD in a j? y e x t r a c t i o n o f t h e
e s p a r t o g r a s s w it h sodium h y d r o x id e s o l u t i o n was
accom panied by a l o s s i n p e n t o s e c o n t e n t , f r o m which
i t f o l l o w s t h a t t h e maximum amount o f p e n t o s a n p r e s e n t
i n e s p a r t o c e l l u l o s e may be s l i g h t l y h i g h e r t h a n t h e
r e s u l t s q u o te d above s e r v e t o i n d i c a t e .
B e f o r e d e a l i n g w ith t h e p rep aeration and
h y d r o l y s i s o f e s p a r t o c e l l u l o s e a c e t a t e , i t i s c o n v e n i e n t
t o s t a t e t h a t t h e p e n t o s a n c o n s t i t u e n t was i d e n t i f i e d
a s x y la n by t h e a c t u a l i s o l a t i o n o f x y l o s e from e s p a r t o
c e l l u l o s e . T h i s was c a r r i e d o u t by b o i l i n g t h e c e l l u l o s e
w i t h / a 12 p e r c e n t s o l u t i o n o f sodium h y d r o x i d e ,
and t h e r e a f t e r p r e c i p i t a t i n g t h e p e n t o s a n from t h e
a l k a l i n e l i q u o r s by t h e a d d i t i o n o f 90 p e r c e n t e t h y l
a l c o h o l . T h e r e s u l t i n g p e n t o s a n was a w h it e powder
e a s i l y decom posed by h e a t , a n d on h y d r o l y s i s vrLth 2
p e r cenÿ s u l p h u r i c a c i d , g a v e a good y i e l d o f c r y s t a l l i n e
x y l o s e .
The a c é t y l a t i o n o f e s p a r t o c e l l u l o s e by
B a r n e tt b method d id n o t p r o c e e d so r e a d i l y a s w ith
( 1 6 )
e x p e r iin e n t a l c o n d i t i o n s , a lD o s t q u a n t i t a t i v e y i e l d s
o f a u n ifo r r j a c e t a t e were o b t a i n e d , c a l c u l a t e d on t h e
b a s i s o f a f i x t u r e o f a t r i a c e t a t e o f (C^H^^O,.)j^,and
a d i a c e t a t e o f (C^Hg C^)^,in t h e r a t i o o f 8 2 p e r c e n t
t o IB p e r c e n t .T h e s iiD u lt a n e o u s h y d r o l y s i s and
c o n d e n s a t i o n o f e s p a r t o c e l l u l o s e a c e t a t e w ith a c i d
D e t h y l a l c o h o l was c a r r i e d ou t i n a manner s i m i l a r
t o t h a t d e s c r i b e d i n t h e c a s e o f c o t t o n c e l l u l o s e
a c e t a t e and t h e p r o d u c t which was i s o l a t e d a f t e r
h y d r o l y s i s p ro v ed t o be a mijcture o f m e t h y l g l u c o s i d e
and m e t h y l x y l o s i d e ,
As r e g a r d s t h e q u a n t i t a t i v e n a tu r e o f t h i s
s e r i e s o f e x p e r i m e n t s , t h e o v e r - a l l y i e l d o f g l u c o s e
amounted t o 9 1 p e r c e n t and t h a t o f x y l o s e t o 7 6 p e r
c e n t o f t h e q u a n t i t i e s t h e o r e t i c a l l y o b t a i n a b l e . '
The low y i e l d o f x y l o s e was d o u b t l e s s due t o t h e
d e s t r u c t i o n o f p e n t o s e d u r in g t h e s e a l e d tu b e t r e a t m e n t .
I t s h o u ld a l s o be s t a ,t e d t h a t t h e above r e s u l t s are
n o t b a s e d on any one s i n g l e e x p e r i m e n t , but have
b een c o n fir m e d i n d u p lic a t e ,W e may t h e r e f o r e i n f e r
t h a t e s p a r t o c e l l u l o s e i s , t o t h e e x t e n t o f DO p e r c e n t
a t l e a s t , a d e f i n i t e c h e m ic a l s u b s t a n c e i n w hich g l u c o s e
i n t h e r a t i o o f 80 p e r c e n t t o 20 p e r c e n t .
I t h a s a l r e a d y b een m en tio n ed t h a t C ross
and B e v a n ,i n t h e i r book ’’C e l l u l o s e r e g a r d e s p a r t o
c e l l u l o s e a s a p ron ou n ced o x y c e l l u l o s e , and t h e y i e l d
o f f u r f u r a l o b t a i n e d on d i s t i l l a t i o n o f t h e c e l l u l o s e
w it h 1 2 p e r c e n t h y d r o c h l o r i c a c i d , a s a d i r e c t m easure
o f t h e d e g r e e o f o x id a ,t io n .T h e y f a r t h e r s t a t e t h a t
e s p a r t o c e l l u l o s e may be d e o x i d i s e d by p r o lo n g e d
e x p o s u r e t o n e u t r a l o r a l k a l i n e r e d u c i n g a g e n t s , a n d
by s o l u t i o n a s t h i o c a r b o n a t e f o l l o w e d by r e g e n e r a t i o n
o f t h e c e l l u l o s e by h e a t i n g t h e s o l u t i o n a t 80^ t o 10(f.
They fou n d t h a t when e s p a r t o c e l l u l o s e was ex p o se d
f o r some tim e t o t h e a c t i o n o f a s o l u t i o n o f z i n c
sodium h y p o s u l p h i t e , p r e p a r e d by t h e a c t i o n o f z i n c
d u s t on sodium b i s u l p h i t e , t h e y i e l d o f f u r f u r a l was
r e d u c e d from 1 2 . G p e r c e n t t o 8 . 9 p e r c e n t , a n d t h a t
e s p a r t o c e l l u l o s e r e g e n e r a t e d from s o l u t i o n a s t h i o
-c a r b o n a t e y i e l d e d o n ly 2 p e r -c e n t o f f u r f u r a l , w h i le
t h e w e ig h t o f t h e r e g e n e r a t e d c e l l u l o s e amounted o n ly
t o 80 p e r c e n t . o f t h e w e ig h t o f c e l l u l o s e o r i g i n a l l y
d i s s o l v e d .
I t i s now c l e a r t h a t e s p a r t o c e l l u l o s e must
( 1 8 )
o x y c 3 l l u l o s e .The y i e l d o f f u r f u r a l o b t a i n e d on d i s t i l l i n ?
t h e c e l l u l o s e w ith 12 p e r c e n t h y d r o c h l o r i c a c i d h a s
b een shewn t o be a q u a n t i t a t i v e m easure o f t h e aDount
o f p e n t o s a n p r e s e n t a s xylan^and t h e e f f e c t s which
C ro ss and Bevan a t t r i b u t e t o d e o x i d a t i o n may be Dore
c o r r e c t l y e x p l a i n e d a s b e in ^ due t o t h e p a r t i a l r é n o v a i
o f t h e x y la n component o f t h e n i x e d c e l l u l o s e .
The p r e s e n t w ork,v/hich was d e s i g n e d a s an
e x t e n s i o n o f t h e r e s e a r c h e s o u t l i n e d above nay be
c o n v e n i e n t l y d i v i d e d i n t o two p a r t s .
(A) The f i r s t s e r i e s o f e x p e r im e n t s v/as d e s i c n e d w ith
tv/o n a i n o b j e c t s i n v i e w :
-( 1 ) To d e te r m in e v/hether t h e h e x o sa n and p e n t o s a n
com ponents o f e s p a r t o c e l l u l o s e a r e i n c h e m ic a l
c o m b i n a t i o n , o r a l t e r n a t i v e l y , m e c h a r i c a l l y m ixed o r
fo r m in g a s o l i d s o l u t i o n .
( 2 ) To d e t e r m in e t h e n a t u r e o f t h e h e x o s e r e s i d u e i n
e s p a r t o c e l l u l o s e , and t o compare i t v/ith t h e h e x o s e
r e s i d u e d e r i v e d from c o t t o n c e l l u l o s e .
(B ) The s e c o n d p a r t o f t h e p ap er d e a l s v/ith t h e p o s s i b i l i t y
o f o b t a i n i n g t r u e d e p o l y n e r i s a t i o n p r o d u c t s o f c e l l u l o s e
by means o f a c e t o l y s i s v/ith a m ix tu r e o f a c e t i c
p o i n t s t o t h e i d e a t h a t t h e s t r u c t u r a l b a s i s o f t h e
com p lex c e l l u l o s e D o l e c u l e i s a t r i a n h y d r o - r l u c o s e ,
THE COMPOSITION OF ESPARTO CELLULOSE.
A la a t t e r o f no su a l l i n t e r e s t t o t h e i n v e s t i g a t o r
o f e s p a r t o c e l l u l o s e i s t h e p r e s e n c e o f t h e p e n t o s a n
c o n s t i t u e n t w hich i s composed o f x y l o s e r e s i d u e s .
The q u e s t i o n o f t h e mechanism o f t h e f o r m a t io n o f
p e n t o s e s i n p l a n t s i s s t i l l t o a g r e a t e x t e n t sh rou d ed
i n o b s c u r i t y , b u t R a v e n n a , ( A t t i , R . A c c a d . L i n c e i , 1 9 0 9 ,
( V) , 1 8 , i i , 1 7 7 ) , c o n c l u d e s t h a t t h e s im p le s u g a r s
r a t h e r t h a n t h e com p lex c a r b o h y d r a t e s e x e r t t h e ma,jor
i n f l u e n c e on t h e i r f o r m a t io n .T h e p e n t o s e component
o f e s p a r t o c e l l u l o s e may be e l a b o r a t e d i n d e p e n d e n t l y
b u t i n t h e same manner a s t h e h e x o s a n c o n s t i t u e n t ,
b u t on t h e o t h e r hand i t may r e s u l t a s a d e g r a d a t i o n
p r o d u c t o f t h e h e x o sa n c o n s t i t u e n t .
I t i s p o s s i b l e , by t h e d e g r a d a .tio n method o f
Vfohl, t o o b t a i n D - a r a b in o s e from D - g l u c o s e ,and i n t h e
same way D - x y l o s e may be o b t a i n e d from D - g u l o s e . I f ,
t h e n , t h e p e n t o s e s form ed i n n a tu r e are d e g r a d a t i o n
p r o d u c t s o f h e x o s e s , we m iglit on f i r s t c o n s i d e r a t i o n s
( 2 0 )
w it h g l u c o s e i n p l a n t s . O n e x e in in in r t h e c o n f i g u r a t i o n s
o f c l ^ c o s e , a r a M n o s e and x^’l o s e , h o v f e v e r , i t becom es
e v i d e n t t h a t a n o t h e r t y p e o f d e g r a d a t i o n i s p o s s i b l e .
J
HO . . . ( 1 ) —Oil II—0—CHOOHHO— 4 H(
H-C-OH
H0-C-4I HO-C-il
H-C-OH 4 H-C-OH
H-C-OH H-C-OH
-OH II-C-OH
H-6-0H CI^OII
[j^OH.
. . (e)
D- r l n 0 0 s e D - x v l o s e D - a r a b in o s e D - r ln co so
I t i s c l e a r t h a t by t h e n e th o d o f Wohi t h e carbon
atoD which i s e l i m i n a t e d from g l u c o s e d u r in g d e g r a d a t i o n
t o a r a b i n o s e i s t h a t which i s d e n o te d by number ( 1 )
i n t h e above f o r m u l a . I f , h o w e v e r ^ it were p o s s i b l e t o
e l a b o r a t e a scheme by w hich d e g r a d a t i o n would p r o c e e d
w it h e l i m i n a t i o n o f t h e ca rb o n atom d e n o te d by number
( 6 ) , t h e r e s u l t i n g p r o d u c t would be x y l o s e and n o t
a r a b i n o s e .S u c h a p r o c e s s o f d e g r a d a t i o n h a s n o t y e t
b e e n a c h i e v e d by c h e m ic a l m e a n s,b u t i t i s by no means
i m p o s s i b l e t h a t su ch a t r a n s f o r m a t i o n may be c a r r i e d
o u t i n t h e p l a n t .
I t a p p e a red p r o b a b le t h a t some i n f o r m a t i o n
l e o b t a i n e d by o u b B i t t i n c i t t o grad ed a c e t o l y a i s ,
f o r , a s h a s a l r e a d y b e e n p o i n t e d o u t , t h i s p r o c e s s
when a p p l i e d t o c o t t o n c e l l u l o s e , may be a r r e s t e d a t
a s t a g s when t h e o c t a c e t a t e o f c e l l o b i o s e i s a
d e f i n i t e p r o d u c t o f t h e r e a c t i o n . I f , t h e r e f o r e , t h e
h e x o s a n and p e n t o s a n c o n p o n e n ts o f e s p a r t o c e l l u l o s e
a r e i n c h e B i c a l c o m b i n a t i o n , i t seem s r e a s o n a b l e t o
e x p e c t t h a t , b y t h e a p p l i c a t i o n o f t h e same p r o c e s s ,
a t l e a s t t r a c e s o f a h e x o s e - p e n t o s e com p ou n d ,of t h e
same t y p e a s c e l l o b i o s e o c t a c e t a t e , m igh t be form ed .
The method which was a d o p ted was a c e t o l y s i s
by means o f a m ix t u r e o f a c e t i c a n h y d rid e and s u l p h u r i c
a c i d a s d e s c r i b e d by Haworth and H i r s t i n t h e f o l l o w i n g
p r e p a r a t i o n o f c e l l o b i o s e o c t a c e t a t e from f i l t e r p a p e r ,
(T. , 1 9 3 1 , 1 1 9 , 1 9 3 ) . "Twenty grams o f f i l t e r p a p e r were
s t i r r e d i n t o a w a t e r - c o o l e d m ix tu r e o f B O c c .o f a c e t i c
a n h y d r id e and l l c c . o f c o n c e n t r a t e d s u l p h u r i c a c i d .
At t h i s s t a g e t h e te m p e r a t u r e o f t h e v i s c i d m ix tu r e
was k e p t j u s t b e lo w 20®.Under t h e p r e s c r i b e d c o n d i t i o n s
a v i s c i d p a s t e vaas form ed a f t e r s t i r r i n g t h e pamper
w it h t h e r e a g e n t s f o r f i v e m in u t e s .A b a t h , c o n t a i n i n g
c a l c iu m c h l o r i d e and w a t e r , h a v i n g b een h e a t e d i n
( 2 2 )
t h e v i s c i d p a s t e o f im p r e g n a te d f i l t e r p a p e r v/'as
h e a t e d hy t h i s m ea n s,a n d t h e c o n t e n t s t h o r o u g h l y
s t i r r e d . R a p i d d i s i n t e g r a t i o n and s o l u t i o n o f t h e
p a p e r o c c u r r e d ;th e m ix t u r e d ark en ed i n c o l o u r ;and,
a t ab ou t 112^assumed t h e form o f a d a r k - r e d m o b ile
l i q u i d ; w h i c h b eg a n t o b o i l . T h i s marked t h e c r i t i c a l
s t a g e i n t h e a c e t o l y s i s p r o c e s s . I m m e d i a t e l y t h e red
s o l u t i o n a p p ea red t o be c h a n g in g t o b l a c k , t h e w hole
o f i t was p o u r ed i n t o one and a h a l f l i t r e s o f c o l d
w a t e r , and a p a l e - y e l l o w p r e c i p i t a t e o f crude c e l l o b i o s e
o c t a c e t a t e s e p a r a t e d o u t a f t e r t e n m i n u t e s ’,'
S e v e r a l e x p e r i m e n t s were c a r r i e d o u t u nder
c o n d i t i o n s i d e n t i c a l \7ith t h o s e d e s c r i b e d a b o v e ,b u t
i n each i n s t a n c e e j c t e n s i v e c h a r r i n g o f t h e m a ,te r ia l
t o o k p l a c e , and o n l y v e r y s m a l l y i e l d s o f a d i s c o l o u r e d
amorphous powder v/ere i s o l a t e d . H a v / o r t h and H i r s t l a y
some s t r e s s on t h e f a c t t h a t t h e c o l o u r c h a n g e s ,
a p p a r e n t i n t h e s o l u t i o n o f f i l t e r pa.per d u r in g
a c e t o l y s i s , s e r v e a s a f a i r i n d i c a t i o n o f t h e p r o g r e s s
o f t h e r e a c t i o n . I n t h e p r e s e n t c a s e t h e i n i t i a l
s o l u t i o n o f t h e e s p a r t o c e l l u l o s e was accom p an ied by
t h e d e v e lo p m e n t o f a dark-brow n c o l o u r , a n d i t was
o f t h i s c o l o u r , t h e D ost:/ o p p o r tu n e s o D e n t f o r t h e
p r e c i p i t a t i o n o f t h e d i s s o l v e d p r o d u c t s w it h w a t e r .
The p h y s i c r l s t a t e o f t h e c e l l u l o s e a p p e a red t o h ave
an im p o r t a n t "bearing on t h e r e a c t i o n , a n d i t v/as
fo u n d t h a t t h e a n ou n t o f c h a r r i n g was s l i g h t l y
d i m i n i s h e d by t h e u s e o f c e l l u l o s e i n a v e r y f i n e
s t a t e o f d i v i s i o n . A f a r t h e r s e r i e s o f e x p e r im e n t s
was now u n d e r t a k e n , i n w hich t h e c o n d i t i o n s o f a c e t o l y s i s
were m o d i f i e d b o th w it h r e g a r d t o t h e te m p e r a t u r e o f
t h e r e a c t i o n and t h e c o n c e n t r a t i o n o f t h e r e a g e n t s ,
b u t i n e v e r y c a s e t h e p r o d u c t s which v/ere i s o l a t e d ,
a lt h o u g h p a r t l y s o l u b l e i n h o t 90 p e r c e n t e t h y l
a l c o h o l , p r o v e d t o be e n t i r e l y amorphous,No t r a c e o f
a h e x o s e - p e n t o s e compound v/as d e t e c t e d ," b u t a, f a c t o f
s t r i k i n g im p o r ta n c e w hich v / i l l be d e a l t v /ith l a t e r , '
was t h e e n t i r e a b s e n c e o f c e l l o b i o s e o c t a c e t a t e from
t h e p r o d u c t s v/hich v/ere o b t a i n e d i n b o th s e r i e s o f
e x p e r i m e n t s .
In c o n j u n c t i o n w it h t h e f o r e g o i n g , a , c e t o l y s i s
e x p e r im e n t s were c a r r i e d o u t a t room t e m p e r a t u r e by
t h e same m e t h o d ,w it h a v ie v / t o e s t i m a t i n g t h e e f f e c t
o f t h e r e a c t i o n on t h e p e n t o s a n c o n s t i t u e n t o f t h e
C24)
a c o l d f i x t u r e o f O O c c .o f a c e t i c a n h y d r id e and 1 2 c c .
o f c o n c e n t r a t e d s u l p h u r i c a c i d , and p r e c a u t i o n s a n a i n s t
l o c a l h e à t i n g d u r in g t h e i n i t i a l s t a g e s o f s o l u t i o n
were ta lcen .T h e c e l l u l o s e d i s s o l v e d v e r y s l o w l y w ith
t h e d e v e l o p u e n t o f t h e brown c o l o u r w hich a p p e a r s t o
be t y p i c a l o f e s p a r t o c e l l u l o s e . VThen t h e c e l l u l o s e
had d i s s o l v e d c o m p l e t e l y t h e r e a c t i o n m ix t u r e was
p oured i n t o a l a r g e e x c e s s o f d i s t i l l e d w a t e r , and t h e
r e s u l t i n g c r e a m y -w h it e p r e c i p i t a t e was washed and d r i e d .
In some e x p e r i m e n t s t h e r e a c t i o n was c o n t i n u e d f o r
t w e n t y - f o u r o r f o r t y - e i g h t h o u r s a f t e r c o m p le te
s o l u t i o n o f t h e c e l l u l o s e had b e e n e f f e c t e d , i n which
c a s e s t h e y i e l d s o f s o l i d p r o d u c t s o f t h e r e a c t i o n
were g r e a t l y d i m i n i s h e d . The s o l i d p r o d u c t s o f a c e t o l y s i s
were c r e a m y -w h ite amorphous p o w d e r s , w h i c h , w it h o u t
f a r t h e r p u r i f i c a t i o n , w e r e shewn by elem en ta-ry a n a l y s i s
t o c o r r e s p o n d r o u g h l y vd.th t r i a c e t a t e s o f c e l l u l o s e .
P e n t o s e e s t i m a t i o n s by t h e f u r f u r a l m ethod shswed
t h a t t h e p e n t o s a n c o n t e n t had f a l l e n from 20 p e r c e n t
t o 11 p e r c e n t , a n d i n some c a s e s t o 8 p e r c e n t .T h e
a c e t o l y s i s o f e s p a r t o c e l l u l o s e t h e r e f o r e r e s u l t s
i n t h e p a r t i a l re m o v a l o f t h e p e n t o s a n c o n s t i t u e n t ,
i s a llo w e d t o p r o c e e d .l- îo r e o v e r ,a n e*^ai3i n a t i o n o f t h e
iDother l i q u o r s a f t e r p r e c i p i t a t i o n o f t h e s o l i d p r o d u c t s
h r o u r h t t o l i r h t t h e f a c t t h a t t h e p e n t o s a n co u p o n e n t
i s n o t "broken down t o f u r f u r a l , "but i s rem oved a s
solu"ble p e n t o s e o r p e n t o s a n a c e t a t e s . ^
T h is e v i d e n c e 31alien i n c o n j u n c t i o n w ith t h e
f a c t t h a t t h e p e n t o s a n c o n s t i t u e n t Day "be c o D p l e t e l y
e x t r a c t e d froD e s p a r t o c e l l u l o s e i n t h e f o r n o f x y l a n
"by t r e a t n e n t w it h " b o ilin c a l k a l i3p o i n t s t o t h e i d e a
t h a t t h e p e n t o s a n and h e x o s a n c o n p o n e n t s a r e n o t i n
c h e m ic a l u n i o n , b u t a re m e c h a n i c a l l y m ixed o r form
( 2 6 )
THE HEXOSlg RESIDUS III ESPARTO CELLULOSE.
I n t h e c o u r s e o f t h e e x p e r i m e n t s a l r e a d y d e s c r i b e d ,
i n w hich e s p a r t o c e l l u l o s e was t r e a t e d w it h a m ix tu r e
o f a c e t i c a n h y d r id e and s u l p h u r i c a c i d u n d er v a r i e d
c o n d i t i o n s o f c o n c e n t r a t i o n and t e m p e r a t u r e , no t r a c e
o f c r y s t a l l i n e m a t t e r was d e t e c t e d i n any o f t h e
s o l i d p r o d u c t s o f a c e t o l y s i s . T h e e n t i r e a b s e n c e o f
c e l l o b i o s e o c t a c e t a t e from t h e s e p r o d u c t s seem s t o
i n d i c a t e t h a t t h e h e x o s e r e s i d u e p r e s e n t i n e s p a r t o
c e l l u l o s e i s o f a d i f f e r e n t c o n s t i t u t i o n a l t y p e from
t h a t p r e s e n t i n c o t t o n c e l l u l o s e , b u t a t t h e same tim e
i t i s c l e a r t h a t t h e p r e s e n c e o f a c o n s i d e r a b l e
p e n t o s a n c o n s t i t u e n t may i n t r o d u c e c o m p l i c a t i o n s o f
a f a r - r e a c h i n r ; n a t u r e i n t o t h e p r o c e s s o f a c e t o l y s i s .
From su c h c o n s i d e r a t i o n s i t was c o n s i d e r e d
d e s i r a b l e t o r e p e a t t h e e x p e r i m e n t s w it h e s p a r t o
c e l l u l o s e from vfhich t h e p e n t o s a n c o n s t i t u e n t had
b e e n r e m o v e d ,‘’N orm al" e s p a r t o c e l l u l o s e was t h e r e f o r e
s u b m i t t e d t o r e p e a t e d e x t r a c t i o n s vdLth 12 p e r c e n t
a l k a l i a t 9 ( f , u n t i l t h e washed and d r i e d f e s i d u e y i e l d e d
N o t e .
o n l y t r a c e s o f f u r f u r a l on d i s t i l l a t i o n \r±th 1 3 p e r
c e n t h y d r o c h l o r i c a c i d , a n d i t was fo u n d t h a t an
" e x t reacted e s p a r t o c e l l u l o s e ", c o n t a in in g ; o n l y v e r y
s l i c ' h t t r a c e s o f p e n t o s a n , D i r h t he o b t a i n e d a f t e r
t h r e e su ch t r e a t m e n t s . T h e e x t r a c t e d m a t e r i a l was u s e d
i n a s t a t e o f f i n e d i v i s i o n i n a s e r i e s o f e x p e r i m e n t s ,
d u p l i c a t e w it h t h o s e a l r e a d y d e s c r i b e d i n t h e c a s e
o f t h e normal c e l l u l o s e , and u nd er s u i t a b l e c o n d i t i o n s ,
a y i e l d o f c e l l o b i o s e o c t a c e t a t e , c o r r e s p o n d in g w it h
1 7 . 5 p e r c e n t o f t h e w e ig h t o f c e l l u l o s e u s e d ,w a s
o b t a i n e d .C o n t r o l e x p e r i m e n t s vrith c o t t o n c e l l u l o s e
u n d e r t h e same c o n d i t i o n s £:ave y i e l d s o f c e l l o b i o s e
o c t a c e t a t e c o r r e s p o n d i n g w it h 19 p e r c e n t o f t h e
w e i g h t o f c e l l u l o s e u s e d .
T h i s r e s u l t a f f o r d s v a l u a b l e c o n f ir m a t o r y
e v i d e n c e t h a t t h e h e x o s e r e s i d u e w hich i s p r e s e n t i n
e s p a r t o c e l l u l o s e i s o f t h e same c o n s t i t u t i o n a l t y p e
a s th a .t p r e s e n t i n c o t t o n c e l l u l o s e . I t a p p e a r s ,h o w e v e r ,
t h a t t h e f o r m a t i o n o f c e l l o b i o s e o c t a c e t a t e from
norm al e s p a r t o c e l l u l o s e i s i n h i b i t e d by t h e p r e s e n c e
o f t h e p e n t o s a n c o n s t i t u e n t . T h e r e a s o n f o r su ch an
e f f e c t i s o b s c u r e , b u t a l i t t l e l i r h t may be throw n
( 2 8 )
a q u a l i t a t i v e n a t u r e shevæcl t h a t t h e x y l a n , o b t a i n e d
by t h e e x t r a c t i o n o f e s p a r t o c e l l u l o s e w it h a l k a l i ,
was e x c e e d i n g l y r é s i s t e n t t o a c e t y l a t i o n . l t seeDS
n o t i m p r o b a b l e , t h e r e f o r e , t h a t a s t h e p e n t o s a n c o n s t i t u e n t
i s u n i f o r m l y d i s t r i b u t e d t h r o u g h o u t t h e h e x o s a n
c o n s t i t u e n t , t h e r e s i s t a n c e o f t h e p e n t o s a n t o a c e t o l y s i s
may im pede o r mask t h e h y d r o l y s i s o f t h e h e x o s a n
c o n s t i t u e n t by a p r o t e c t i v e i n f l u e n c e ,w hich may be
compared i n e f f e c t w it h s t e r i c h i n d r a n c e .
A s y s t e m a t i c s t u d y o f e x t r a c t e d e s p a r t o
c e l l u l o s e was now c a r r i e d o u t .
The e x t r a c t e d m a t e r i a l ,\7hich i n v a r i a b l y
c o n t a i n e d a h i g h e r p e r c e n t a g e o f ash t h a n t h e norm al
c e l l u l o s e , v/as a c e t y l a t e d e s s e n t i a l l y i n a c c o r d a n c e
w it h t h e method o f B a r n e t t , i n w hich s u l p h u r y l c h l o r i d e
i s u s e d a s t h e c a t a l y s t , b u t t h e r e a c t i o n t o o k p l a c e
v e r y s l o v / l y and w it h g r e a t d i f f i c u l t y .C o n s t a n t
m e c h a n ic a l s t i r r i n g was n e c e s s a r y , and t h e c o m p le te
s o l u t i o n o f t h e c e l l u l o s e was n o t e f f e c t e d u n t i l t h e
e x p e r im e n t had b e e n i n p r o g r e s s f o r o v e r t v /e n ty h o u r s ,
d u r in g v/hich t im e s e v e r a l s u c c e s s i v e t r e a t m e n t s w ith
c h l o r i n e and s u lp h u r d i o x i d e v/ere g i v e n t o t h e m i x t u r e .
o f t h e a a c u n t o f a c e t a t e a v a i l a b l e on t h e b a s i s o f
a t r i a c e t a t e o f c e l l u l o s e were o b t a i n e d , w h i l e i n a
f a r t h e r e x p e r i i a e n t , i n v/hich e l a b o r a t e p r e c a u t i o n s
a r a i n s t l o s s o f m a t e r i a l v/ere t a l i e n , t h e y i e l d
c o r r e s p o n d e d v /ith 95 p e r c e n t o f t h e t h e o r e t i c a l
am ount.The e x t r a c t e d e s p a r t o a c e t a t e d i f f e r e d from
t h e t y p i c a l c o t t o n c e l l u l o s e a c e t a t e i n s e v e r a l
r e s p e c t s . l t was much b u l k i e r ;v/as n o t so h ard and
c r i s p ;and v/as creamy i n c o l o u r r a t h e r t h a n p u re v / h i t e .
An e le m e n t a r y a n a l y s i s o f t h e a c e t a t e shev/ed t h a t i t
c o r r e s p o n d e d v /ith a t r i a c e t a t e o f c e l l u l o s e ,
PtHyO, (O^COO)^^.
SIMULTANEOUS HYDROLYSIS AND CONDENSATION OF THE ACETATE
7/ITII ACID METHYL ALCOHOL.
I n o r d e r t o c o n v e r t t h e e x t r a c t e d e s p a r t o c e l l u l o s e
a c e t a t e i n t o m e t h y l g l u c o s i d e i t v/as t r e a t e d v/ith
a c i d m e th y l a l c o h o l i n s e a l e d t u b e s ,v /h e n i t v/as
i n v a r i a b l y fo u n d t o be much more r e s i s t a n t t h a n e i t h e r
t h e normal c o t t o n o r e s p a r t o c e l l u l o s e a c e t a t e s .
C o n c e n t r a t i o n s o f h y d r o g en c h l o r i d e from 1 p e r c e n t
t o 3 p e r c e n t , a n d c o n d i t i o n s o f t e m p e r a t u r e r a n g in g
( 3 0 )
e x p e r i m e n t s ;b u t a l l e f f o r t s t o e f f e c t c o m p le t e
s o l u t i o n o f t h e a c e t a t e were u n a v a i l i n g . I n e v e r y
e x p e r im e n t p a r t i a l s o l u t i o n o f t h e a c e t a t e was
a cc o m p a n ied by t h e d e v e lo p m e n t o f a d e e p -b r o w n c o l o u r
and i n mamy causes c h a r r i n g a l s o t o o l p l a c e . O n e o f
t h e m ost s u c c e s s f u l e x p e r i m e n t s , i n which t h e r e was
o n l y a s l i g h t s o l i d r e s i d u e and d e v e lo p m e n t o f c o l o u r ,
y i e l d e d a dark and o n l y p a r t i a l l y c r y s t a l l i n e s y r u p ,
c o r r e s p o n d i n g i n amount vn.th 8 3 . 5 p e r c e n t o f t h e
t h e o r e t i c a l q u a n t i t y o f c r y s t a l l i n e m e t h y l g l u c o s i d e .
I t s h o u l d be n o t e d th cit t h e t h e o r e t i c a l q u a n t i t y was
c a l c u l a t e d on t h e a s s u m p t io n t h a t t h e a c e t a t e was
composed e n t i r e l y o f g l u c o s e r e s i d u e s . B y r e c r y s t a l l i s i n g
t h i s s y r u p from e t h y l a c e t a t e , t h e amount o f pure
c r y s t a l l i n e m e t h y l g l u c o s i d e w hich was o b t a i n e d
c o r r e s p o n d e d w it h 4 2 p e r c e n t o f t h e t h e o r e t i c a l q u a n t i t y
As i t a p p e a red p r o b a b l e t h a t t h e p h y s i c a l
s t a t e o f t h e a c e t a t e m ig h t h a v e a r e t a r d i n g i n f l u e n c e
on t h e r e a c t i o n , a n a t t e m p t was made t o o b t a i n i t i n
a more r e a c t i v e fo rm .T lie a c e t a t e was d i s s o l v e d i n
c h lo r o f o r m i n a C a r iu s t u b e , a n d an e q u a l volum e o f
m e t h y l a l c o h o l was added a l o n g w i t h s u f f i c i e n t a c i d
m e th y l a l c o h o l t o g i v e a 1 p e r c e n t c o n c e n t r a t i o n o f
p r e c i p i t a t e d t h e a c e t a t e ao a j e l l y - l i k e m a s s ,a n d i t
WO.G c o n s i d e r e d t h a t i n t h i s s t a t e t h e coDponnd D i r h t
r e a c t more r e a d i l y v /ith t h e D e t h y l a l c o h o l and h y d r o g e n
c h l o r i d e . V e r y l i t t l e c o l o u r d e v e l o p e d i n t h i s e x p e r i m e n t ,
"but t h e s o l i d r e s i d u e v/ p .s c o n s id e r a " b le , and t h e sy r u p
w hich v/as f i n a l l y i s o l a t e d v/a-s a g a i n v e r y dark i n
c o l o u r and o n l y p a r t i a l l y c r y s t a l l i n e ,
T r e a t D e n t o f t h e a c e t a t e w it h h i g h l y i n c r e a s e d
c o n c e n t r a t i o n s o f h y d r o g e n c h l o r i d e i n m e t h y l a l c o h o l
v/as now r e s o r t e d t o .The f i n e l y pov/dered a c e t a t e v/as
su sp e n d e d i n c o l d m e t h y l a l c o h o l and dry h y d r o g e n
c h l o r i d e v/as p a s s e d i n t o t h e s o l u t i o n u n t i l i t v/as
s a t u r a t e d . T i l 3 m ix t u r e v/as k e p t i n a s t o p p e r e d f l a s k
w i t h o c c a s i o n a l s h a k i n g f o r s i x days,"by v/hich t im e
t h e a c e t a t e had a lm o s t c o m p l e t e l y d i s s o l v e d . A f t e r t h e
e l i m i n a t i o n o f t h e e x c e s s a c i d and n e u t r a l i s a t i o n ,
t h e syrup v/hich was i s o l a t e d c r y s t a l l i s e d c o m p l e t e l y
on n u c l é a t i o n v /ith m e t h y l g l u c o s i d e , and t h e y i e l d i n
t h i s c a s e amounted t o 64 p e r c e n t o f t h e t h e o r e t i c a l
q u a n t i t y .
From t h e g e n e r a l c o u r s e o f t h e s e e x p e r i m e n t s
i t i s c l e a r t h a t t h e h e x o s a n r e s i d u e d e r i v e d from
e s p a r t o c e l l u l o s e "by t h e e x t r a c t i o n o f t h e p e n t o s a n
( 3 2 )
o r t h a t t h e p r o lo n r e c l t r e a t m e n t o f t h e f i b r e s o f t lie
e s p a r t o w i t h b o i l i n g a l k a l i h a s r e s u l t e d i n c o n s i d e r a b l e
c h a n c e s i n t h e c e l l u l o s e .The l a t t e r v ie w se eio s n o t
u n l i k e l y when t h e d r a s t i c n a t u r e o f su c h t r e a t m e n t
w it h s t r o n g a l k a l i i s tal^en i n t o a c c o u n t ,a n d t o
d e c i d e t h i s p o i n t , i t a p p e a r e d d e s i r a b l e t o t e s t t h e
b e h a v io u r o f n o r n a l c o t t o n c e l l u l o s e a f t e r a s i i a i l a r
t r e a t m e n t w it h alkoJLi.
ANALOGOUS EXPERIH5ITTS WITH COTTON
CELLULOSE.-C o tto n c e l l u l o s e v/’a s a c c o r d i n g l y h e a t e d v/ith a 12 p e r
c e n t s o l u t i o n o f sodiura h y d r o x id e f o r n i n e h o u r s a t
90% a f t e r v/hich t h e v/ashed and d r i e d r e s i d u e v/as
a c e t y l a t e d a s b e f o r e . A s f a r a s a c é t y l a t i o n v/as c o n c e r n e d ,
'th e c o t t o n c e l l u l o s e d id n o t ap p e a r t o h ave b e e n
a p p r e c i a b l y a l t e r e d by t h e t r e a t m e n t v /ith a l k a l i ,
f o r t h e r e a c t i o n p r o c e e d e d n o r m a lly v /it h o u t t h e a i d
o f m e c h a n ic a l s t i r r i n g and g a v e a good y i e l d o f
t r i a c e t a t e c o r r e s p o n d i n g v /ith 9 1 p e r c e n t o f t h e
t h e o r e t i c a l maximum.
As i n t h e c a s e o f e x t r a c t e d e s p a r t o c e l l u l o s e
a c e t a t e , t h i s a c e t a t e v/as c o n v e r t e d i n t o m e t h y l g l u c o s i d e
