Styrene maleic anhydride

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Studies on Testis, Sperm Characteristics and Teratogenic aspects after Vas occlusion by a co-polymer of styrene maleic anhydride - RISUG and its reversal in rats

Studies on Testis, Sperm Characteristics and Teratogenic aspects after Vas occlusion by a co-polymer of styrene maleic anhydride - RISUG and its reversal in rats

The non-hormonal contraceptive, named RISUG (an acronym for Reversible Inhibition of Sperm Under Guidance) has expected to provide a valuable addition to the currently limited options of male contraceptio 1 (Ananthaswamy, 2002). RISUG (Mark sans Pharma, Mumbai, India) consists of a co-polymer styrene maleic anhydride (SMA) dissolved in 99.9% pure dimethylsulphoxide (DMSO) (Guha, 1996). A single injection (therapeutic dose of 60 mg SMA in 120 ml of DMSO) bilaterally into the vas deferens of the male in a minimally invasive manner has been shown to cause the disintegration of sperms and leads to necrozoospermia (Chaudhury et al., 2004). SMA is one such agent which when placed in the vas deferens lumen lowers the pH of the luminal micro-environment and inhibits sperm acrosomal reaction within 3h post-injection before the ejaculation in human (Guha, 2007; Sharma et al., 2008). The reported reversal studies of vas occlusion have been shown to cause normospermia with normal sperm motility and viability 30 days after reversal in langur monkeys (Lohiya et al., 1998).
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Synthesis, Characterisation and Haematological Profile of Modified Styrene Maleic Anhydride by Piperazine and Dissolution in DMSO

Synthesis, Characterisation and Haematological Profile of Modified Styrene Maleic Anhydride by Piperazine and Dissolution in DMSO

light and 12 hrs dark photoperiod. The animals were kept in identical environmental condition and were mentioned in pellet diet and water (24 hrs).The selected 8 male rats were divided into 2 groups of 4 rats. The Ist group served as control low dose while IInd group served as treated high dose. For implantation of the polymer complex, lower abdominal area was chosen; minor incision with the help of sharp sterile blade was given of the size 0.5cm. The derived styrene maleic anhydride- piperazine polymer complex was injected into the lumen. Different doses of complex as stated below in Table 3 were given and skin wound was stitched, dressed up with neosprin antibiotic powder. All the rats were kept under strict watch till the healing was completed. Different hematological parameters were recorded in the control low dose as well as the high dose rats and was found as : Total leukocyte count (10 3 /cumm), Total
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A Nano-Composite Based on Fe3O4@Styrene-Maleic Anhydride Copolymer as a Magnetic Sorbent for Preconcentration of Silver(I) Ion

A Nano-Composite Based on Fe3O4@Styrene-Maleic Anhydride Copolymer as a Magnetic Sorbent for Preconcentration of Silver(I) Ion

chelating materials to their surfaces because of their inertness to surrounding environment, ease of surface modification with specific functional groups, and high surface area-to-volume ratio leading to enhancement of adsorption capacity [17]. The interactions between hydroxyl groups on the iron oxide surface and functional groups of organosilane coupling agents not only support terminal functional groups available for connecting to other targeting polymers but also decrease aggregation and enhance dispersion stability [16]. On the other hand, a polymeric ligand is applied to selectively bind with a specific metal ion in a mixture to isolate the target metal ion from aqueous media [18-21]. Styrene-maleic anhydride (SMA) copolymer is a commercial industrial polymer which is cheaper than any other polymers possessing reactive group in the main chain or side chain for further functionalization [22]. In recent years, various studies have been undertaken about metal ions adsorption with the SMA copolymer derivatives [23-25]. To the best of our knowledge, no attempt has been made to apply a magnetic nanocomposite (MNC) based on the modified styrene-maleic anhydride copolymer and Fe 3 O 4 NPs in solid-phase extraction of metal ions.
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Surface Modification of Nanoclays with Styrene Maleic Anhydride Copolymers

Surface Modification of Nanoclays with Styrene Maleic Anhydride Copolymers

This study presents the modification of surfaces of nanoclays, halloysite na- notubes (HNT) and sepiolite (SEP), with styrene-maleic anhydride copoly- mers (SMA) via esterification reaction between hydroxyl groups of the na- noclays and anhydride groups of SMA. The structural, thermal, and morpho- logical analyses of the modified nanoclays were performed by Fourier trans- form infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), thermal gravimetric analysis (TGA), and field emission scanning electron microscopy (FESEM). All of these results suggested that the expected modification of HNT and SEP surfaces were performed. Although XRD patterns of HNT containing samples showed that the basal spacing shifted to higher distances, it was found that those of the crystalline structure of SEP remained un- changed. Thermal gravimetric analysis exhibited that SMA copolymers were grafted onto the surfaces of nanoclays varying amounts between 15 and 43 wt. % depending on the types of nanoclays and SMA copolymers. This mod- ification indicates that these nanoclays can be added to the polystyrene matrix without any compatibilizers.
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Preconcentration of Germanium(IV) on Styrene Maleic Anhydride Copolymer Modified with Aminobenzoic Acids and Its Spectrophotometric Determination with  Bis(2,3,4 trihydroxyphenylazo)benzidine

Preconcentration of Germanium(IV) on Styrene Maleic Anhydride Copolymer Modified with Aminobenzoic Acids and Its Spectrophotometric Determination with Bis(2,3,4 trihydroxyphenylazo)benzidine

The obtained results demonstrate the efficiency of the chemically modified styrene-maleic anhydride copoly- mer sorbents towards selective quantitative sorption (se- paration) and preconcentration of germanium. The sorp- tion is markedly influenced by the used complexing re- agent (modificator), pH and flow rate. In contrast to some other reported sorbents (Table 1) the sudied sor- bent shows better characteristics, i.e., being superior in terms of selectitity, detection limits and dynamic sorption capacity. The separation step results in an analytical sample which is relatively free of interferences of many ions. Favourable features of the described methodology are its low instrument and running costs, easy operation, and high sensitivity. It can be used in routine analysis and can be applied for the determination of ultra-trace germanium in a diversity of objects (environmental and industrial samples) without significant interaction from other cationic species present in the samples.
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Kinetic study of styrene/maleic anhydride copolymers using succine anhydride as the model compound

Kinetic study of styrene/maleic anhydride copolymers using succine anhydride as the model compound

The rate constants with aniline at Compound determined for the polymers 67 degrees Celsius are as and succinic anhydride follows from Table XV: Rate Constant reacted with aniline Deviati[r]

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Synthesized nanoparticles of poly (Styrene–alternative-maleic anhydride) and prunus cerasus rock used for removing Cadmium (II) ions from aqueous solutions

Synthesized nanoparticles of poly (Styrene–alternative-maleic anhydride) and prunus cerasus rock used for removing Cadmium (II) ions from aqueous solutions

purchased from Merck (Germany) and were used without further purification. 1, 4-diamino butane (DAP), styrene, maleic anhydride, melamine, butanedioic acid, benzoyl peroxide, triethylamine (TEA) and the organic solvents, such as tetrahydrofuran (THF) and normal hexane, were also purchased from Merck and were used without further purification. The aqueous solutions were prepared by the dissolution of cadmium salts in deionized water. Shells of the Iranian pit shell (Sour cherry or prunus cerasus rock) (PCR) were used as bio sorbent. IR spectra were measured with a Fourier transform infrared spectrophotometer (Nexus-670, Thermo Nicolet, USA). The X-ray diffraction (XRD) spectra were recorded on a X’pert Philips X-ray photo electron spectrometer (The Netherlands) with non-mono-chromated Mg Ka radiation as the excitation source. Atomic absorption spectrophotometry (AAS; Analytik jenanov AA 400, Germany) was used to determine the metal-ion concentrations in aqueous solutions. The inherent viscosity of the resulting SMA polymer was obtained with an Ostwald Viscometer at 25 °C in a thermostated water bath. The elemental analysis of one of the adsorbents was performed by a CHN analyzer (2400 series II, PerkinElmer Co., USA). The morphology of the particles was examined via scanning electron microscopy (SEM; XL30 Philips, Netherland).
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Biodegradable Polymers Based on Natural Substances

Biodegradable Polymers Based on Natural Substances

This chapter gives a description of the various procedures employed for the linking minute quantities of various monosaccharides and disaccharides onto poly(styrene maleic anhydride). This chapter also overviews the various methods that have been employed previously for the syntheses of biodegradable polymers. The possibility of using other functionalized polymers, other solvent systems, catalysts and work-up procedures have also been discussed. The synthesis of biodegradable polymers by linking of sugars onto functionalized polystyrene by polymer analogous reaction has been covered in a patent (Biodegradable synthetic polymers and process for preparation thereof, Patent Application: Nov. 2002)
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Study of the styrene and maleic anhydride 
		copolymerization process by mathematical modeling methods

Study of the styrene and maleic anhydride copolymerization process by mathematical modeling methods

There is known a way to obtain styrene-maleic anhydride copolymers by a radical copolymerization of styrene and maleic anhydride in cyclohexanone solution at 140-150 °C over 3 wt. % (Poroform CHHK-57). Also there have been known a method where acetone can be used as one of the solvents. The initial ratio of monomers (mol) Styrene: Maleic anhydride - 1: 1, the ratio of monomers to the solvent (module) - 1: 4. Porophore is used as an initiator. In the current technology the process of obtaining stiromal is carried out in a heterogeneous aromatic solvent environment. The copolymer obtained by this method is released in the form of extremely fine dispersion which increases a fire and explosion hazard process. Furthermore, this method is characterized by a low productivity and high flow of deficient aromatic solvents.
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Investigation on Thermal Aging and Mechanical Properties of the Nano-SiO2/Epoxy Adhesive

Investigation on Thermal Aging and Mechanical Properties of the Nano-SiO2/Epoxy Adhesive

In this paper, contents of 1wt% and 2wt% nano-Silica were added into Epoxy Tung-maleic Anhydride Adhesive Resin to study the thermal aging and mechanical properties of the composite. Thermal aging test, flexural property test and impact property test were conduct according to the corresponding standard.

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Chemical Modification of Polypropylene by Maleic Anhydride: Melt Grafting, Characterization and Mechanism - Volume 5 Number 2 (Apr. 2014) - IJCEA

Chemical Modification of Polypropylene by Maleic Anhydride: Melt Grafting, Characterization and Mechanism - Volume 5 Number 2 (Apr. 2014) - IJCEA

Polypropylene was functionalized with different ratios of MA and DCP in optimum processing conditions by melt mixing. The properties of functionalized PP were characterized by titration, FT-IR spectroscopy, Contact angle measurement and thermal analysis. It was concluded that the degree of functionalized PP depends on the concentration of both monomer and initiator. It was found that the increase in peroxide concentration to 4phr resulted in the elevation in the percent reacted MA, and the elevation in the initial maleic anhydride concentration in the reaction mixture led to an increase in percent MA, passing through a maximum value, with posterior decline, The initial increase in the percent grafting is caused by an increase in concentration of radicals formed through the decomposition of initiator, and also it was found that the monomer content from 1 to 3 phr of monomer has satisfied results, but in higher amount of monomer the functionality was decreased, this due to homopolymerization of monomer during processing.
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3 [(4 Bromo­anilino)­carbonyl]­prop 2 enoic acid

3 [(4 Bromo­anilino)­carbonyl]­prop 2 enoic acid

establishes that condensation of 4-bromoaniline with maleic anhydride gives the title compound at room temperature. There are strong intermolecular NÐH O hydrogen bonds [N O = 2.814 (3) AÊ and 2.817 (3) AÊ] linking the molecules into sheets lying parallel to the bc plane. The carboxyl groups adopt an anti-planar conformation and participate in intra- molecular OÐH O hydrogen bonds [O O = 2.484 (3) and 2.487 (3) AÊ]. There are two molecules in the asymmetric unit.

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3 [(2,4,6 Tri­chloro­anilino)­carbonyl]­prop 2 enoic acid

3 [(2,4,6 Tri­chloro­anilino)­carbonyl]­prop 2 enoic acid

The title compound, (I), was synthesized by the condensation of 2,4,6- trichloroaniline with maleic anhydride. To a solution of maleic anhydride (1 mmol) in HOAc (300 ml) was added a solution of 2,4,6- trichloroaniline (1 mmol) in HOAc (150 ml) and the mixture was stirred at room temperature overnight. The light-gray precipitate was ®ltered, washed with cold distilled H 2 O (200 ml) and air dried.

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Effect of Additives on Polypropylene/Kaolin Composite Prepared  via In-situ Process

Effect of Additives on Polypropylene/Kaolin Composite Prepared via In-situ Process

It is therefore noteworthy to observe that the preparation of composite through the commercially modified clay introduces new properties into the composite. Subsequently, direct mixing of the modifiers was utilized in this work. Hence, maleic anhydride and dicumyl peroxide were used simultaneously as additives in the preparation of composite using in-situ process. The investigation seeks to examine the effectiveness of the additives in a successful preparation of the composite.

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SYNTHESIS, CHARACTERIZATION AND ANTI INFLAMMATORY EVALUATION OF SOME NEW 2 (3 FLUOROBIPHENYL 4 YL) PROPANOIC ACID DERIVATIVES

SYNTHESIS, CHARACTERIZATION AND ANTI INFLAMMATORY EVALUATION OF SOME NEW 2 (3 FLUOROBIPHENYL 4 YL) PROPANOIC ACID DERIVATIVES

The refluxing of [3a-d] with some acid anhydride namely maleic anhydride, succinic anhydride and phthalic anhydride gave the corresponding oxazepine derivatives [8a-d], [9a-d] and [10a-d]. The absence of stretching absorption band at (1581-1620) cm -1 for izomethain group (CH=N) and appearance of absorption band which is due to (C=O ring) at (1662-1733) cm -1 , while 1 H-NMR spectrum showed singlet signal at (3.90-4.69) ppm for (C-H oxazepine ring) gave a good evidence for the formation of oxazpine derivatives. Hydrazone derivatives [4a-d] that reacted with phenylisocyanate via a [2+2] cycloaddition reaction
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The compatibilizing effect of polypropylene maleic anhydride (PPMAH) on 
		polypropylene (PP)/acrylonitrile butadiene rubber (NBR)/palm kernel 
		shell (PKS) composites

The compatibilizing effect of polypropylene maleic anhydride (PPMAH) on polypropylene (PP)/acrylonitrile butadiene rubber (NBR)/palm kernel shell (PKS) composites

Salleh, F.M., Hassan, A., Yahya, R., Araga, R.A.L., Azzahari, A.D. and Nazir, M.N.Z.M. 2014. Improvement in the Mechanical Performance and Interfacial Behavior of Kenaf Fiber Reinforced High Density Polyethylene Composites by the Addition of Maleic Anhydride Grafted High Density Polyethylene. Journal Polymer Res, 21, pp. 439.

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Structural and mechanistic studies of sheep liver aldehyde dehydrogenase : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemistry at Massey University, New Zealand

Structural and mechanistic studies of sheep liver aldehyde dehydrogenase : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemistry at Massey University, New Zealand

The ef fect of propionic anhydride o n the NADH burst at high concentrations of propion aldehyde.. The ef fect of maleic anhydride o n the NADH burst at low concentrations of propionalde[r]

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Effect of Wood Flour Mesh Size on Mechanical Properties of Wood Flour Polypropylene (WFPP) Composites Vinay Kumar and Hemant Kumar

Effect of Wood Flour Mesh Size on Mechanical Properties of Wood Flour Polypropylene (WFPP) Composites Vinay Kumar and Hemant Kumar

Wood flour was used as filler in polypropylene, a commodity plastic for making thermoplastic composites by the process of extrusion and compression molding. Adhesion between wood flour and polypropylene was improved by using maleic anhydride polypropylene (MAPP) compatibilizer and optimum level was 1.5% (weight basis) resulting improvement in mechanical properties such as as tensile, impact, flexural and hardness. Improvement in mechanical properties was found by using higher (finer) mesh size wood flour powder. Composites thus prepared have applications in building and automobile industries.
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CONTROLLED DRUG RELEASE OF GRAFTED PECTIN

CONTROLLED DRUG RELEASE OF GRAFTED PECTIN

Modification of Pectin as natural polymer was accepted as new bio adhesive polymer, which was grafted with Maleic anhydride as vinylic monomore and insertion by using ceric ion it, saw substituted with amino drugs produced amide polymer which do not lose their biological properties. This design carries controlled delivery which could release the entrapped drug over an extended period of time due to its slow digesting nature. The prepared adhesive drug polymer waw characterized by FTIR, 1 H-NMR spectroscopes, thermo gravimetric analysis TGA and DSC were careful. Physical properties of prepared polymer waw quiet, Biological activity was studied for adhesive drug polymer, this new adhesive drug biological polymers were applied on different infected mice and wounds, It gave outstanding results and compliance mice infected with a full recovery by a short period of time. The prepared drug copolymer was analyzed in different pH values at 37 0 C in vitro study and controlled drug release was messured through three days . The rate of hydrolysis in basic medium was found higher than acidic medium. It was concluded that modified drug release with extended drug action via slow release and in vivo performance was renowned to be talented.
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Spray-Dried Cellulose Nanofibril-Reinforced Polypropylene Composites for Extrusion-Based Additive Manufacturing: Nonisothermal Crystallization Kinetics and Thermal Expansion

Spray-Dried Cellulose Nanofibril-Reinforced Polypropylene Composites for Extrusion-Based Additive Manufacturing: Nonisothermal Crystallization Kinetics and Thermal Expansion

Abstract: Isotactic polypropylene (iPP) is a versatile polymer. It accounts for the second-largest polymer consumption worldwide. However, iPP is difficult to 3D print via extrusion-based processing. This is attributable to its rapid crystallization rate. In this study, spray-dried cellulose nanofibrils (SDCNF) and maleic anhydride polypropylene (MAPP) were investigated to reveal their effects on the nonisothermal crystallization kinetics and thermal expansion of iPP. SDCNF at 3 wt % and 30 wt % accelerated the crystallization rate of iPP, while SDCNF at 10 wt % retarded the crystallization rate by restricting crystal growth and moderately increasing the nucleation density of iPP. Additionally, adding MAPP into iPP/SDCNF composites accelerated the crystallization rate of iPP. The effective activation energy of iPP increased when more than 10 wt % SDCNF was added. Scanning electron microscopy and polarized light microscopy results indicated that high SDCNF content led to a reduced gap size among SDCNF, which hindered the iPP crystal growth. The coefficient of thermal expansion of iPP/SDCNF10% was 11.7% lower than the neat iPP. In summary, SDCNF, at 10 wt %, can be used to reduce the warping of iPP during extrusion-based additive manufacturing.
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