Styrene-maleic anhydride acrylonitrile terpolymer

Polycarbonate is blended with a number of polymers including PET, PBT, acrylonitrile-butadiene-styrene terpolymer (ABS) rubber, and styrene-maleic anhydride (SMA) copolymer. The blends have lower costs compared to polycarbonate and, in addition, show some property improvement. PET and PBT impart better chemical resistance and processability, ABS imparts improved processability, and SMA imparts better retention of properties on aging at high temperature. Poly(phenylene oxide) blended with high-impact polystyrene (HIPS) (polybutadiene-gra/f-polystyrene) has improved toughness and processability. The impact strength of polyamides is improved by blending with an ethylene copolymer or ABS rubber. 

An appropriate formalism for Mark-Houwink-Sakurada (M-H-S) equations for copolymers and higher multispecies polymers has been developed, with specific equations for copolymers and terpolymers created by addition across single double bonds in the respective monomers. These relate intrinsic viscosity to both polymer MW and composition. Experimentally determined intrinsic viscosities were obtained for poly(styrene-acrylonitrile) in three solvents, DMF, THF, and MEK, and for poly(styrene-maleic anhydride-methyl methacrylate) in MEK as a function of MW and composition, where SEC/LALLS was used for MW characterization. Results demonstrate both the validity of the generalized equations for these systems and the limitations of the specific (numerical) expressions in particular solvents. 

In this paper a generalized approach is presented to the derivation of H-H-S equations for multispecies polymers created by addition polymerization across single double bonds in the monomers. The special cases of copolymers and terpolymers are derived. This development is combined with experimental results to evaluate the numerical parameters in the equations for poly(styrene-acrylonitrile ) (SAN) in three separate solvents and for poly(styrene-maleic anhydride-methyl methacrylate) (S/HA/MM) in a single solvent. The three solvents in the case of SAN are dimethyl formamide (DMF), tetrahydrofuran (THF), and methyl ethyl ketone (MEK) and the solvent for S/HA/HH is HER. 

A group of new, fully miscible, polymer blends consisting of various styrene-maleic anhydride terpolymers blended with styrene-acrylonitrile copolymer and rubber-modified versions of these materials have been prepared and investigated. In particular the effects of chemical composition of the components on heat resistance and the miscibility behavior of the blends have been elucidated. Toughness and response to elevated temperature air aging are also examined. Appropriate combinations of the components may be melt blended to provide an enhanced balance of heat resistance, chemical resistance, and toughness. 

Styrene-maleic anhydride copolymer (SMA) and terpolymers with methyl methacrylate (SMA-MMA) and acrylonitrile (SMA-AN)... 

PP poly(propylene), PS poly(styrene), MAH maleic anhydride, MA methacrylic acid, S styrene, PE poly(ethylene), PPE poly(phenylene ether), LDPE low-density PE, EPDM ethylene-propylene-diene terpolymer, SAN styrene-acrylonitrile copolymer, EPR ethylene-propylene copolymer, NMAC A -methacrylyl caprolactam, GMA glycidyl methacrylate, FA fumaric acid, AEFO anhydride and epoxide functionalized olefin copolymer, SEBS styrene/ethylene-butylene/styrene copolymer, HDPE high-density PE, AN acrylonitrile, and S-MAH-MMA styrene-maleic anhydride-methyl methacrylate copolymer. 

Compatibilization improves the morphological stability of polymer blends when block or graft copolymers are used by the introduction of steric hindrance to drop coalescence. A chemical approach is possible for formation of grafted PC with SAN chains at the PC/SAN interface. SAN-amine copolymer is prepared by reaction of a terpolymer of styrene, maleic anhydride, and acrylonitrile with l-(2aminoethyl) piperazine. The SAN-amine polymer is miscible with the SAN matrix of ABS and reacts with PC. The formation of graft polymer has resulted in the reduction of SAN dispersed-phase particle size. The blend morphology has been found to stabilize in the mixing process. 

Nevertheless, a terpolymer of styrene-maleic anhydride and acrylonitrile (S/MA/AN) met the specifications of superior thermal properties but it was difficult to injection mold using the plunger-type presses available in the early 1940 s. This objection was overcome by blending with NBR, SBR, or HIPS. 

Polybutylcyanoacrylates [63], polyacrylics [64], polybutadiene [65], flame retardant PE [66], PS [67-70], PS - divinyl benzene copolymer [71], PS - acrylonitrile copolymer [72], acrylonitrile-butadiene-styrene terpolymer [73, 74], styrene-maleic anhydride copolymer [75], polyvinyl-cyclohexane [76], polyphenylene triazine [77], poly-4-vinyl pyridine [78], polyethylene sulfide [79], PSF [80], brominated PES [81], tetrafluoroborate doped polythiophene [82], polysiloxane [56, 83], vinyl pyrrolidone-methacryloxy silicone copolymer [50], polyvinyl indene [84], poly-E-lactide [3, 85, 86], epoxy resins [87, 88], polyaryl ether ketone [89, 90], ethylene... 

The SAN and ABS cxjpolymers aantain approximately 25 wt% of acrylonitrile and polybutadiene rubber in amounts up to 20 wt%. Other styrene copolymers of industrial importance include styrene—maleic anhydride copolymer (SMA), styrene-divinylbenzene copolymer, acrylic—styrene-acrylonitrile terpolymer, and styrene-butadiene copolymer. Recently, metallocene catalysts have been developed to synthesize syndiotactic polystyrene (sPS). The polymerization process and process conditions have major effects on polymer properties and process economy. For styrene homopolymerization and copolymerization, various types of polymerization reactors are used commercially. 

B.M. Rao, P.R. Rao, and B. Sreenivasulu, Grafting of maleic anhydride onto acrylonitrile-butadiene-styrene terpolymer Synthesis and characterization, Polym.-Plast. Technol. Eng., 38(5) 967-977, November 1999. 

R. Qi, J. Qian, and C. Zhou, Modification of acrylonitrile-butadiene-styrene terpolymer by grafting with maleic anhydride in the melt. I. Preparation and characterization, J. Appl. Polym. Sci., 90(5) 1249-1254, October 2003. 

R. Qi, Z. Chen, and C. Zhou, Solvothermal preparation of maleic anhydride grafted onto acrylonitrile-butadiene-styrene terpolymer (ABS), Polymer, 46(12) 4098-4104, May 2005. 

Blends of copolymers of styrene and acrylonitrile and butadiene and acrylonitrile called ABS plastics which are more ductile than polystyrene, are now used at an annual rate of almost 500 thousand tons. Terpoljrmers of styrene, acrylonitrile and maleic anhydride (Cadon) have heat deflection points above lOOOC.Q)While the physical properties of both ABS and the maleic anhydride terpolymers are superior to polystyrene, the improvements are not sufficient to classify them as high performance plastics. 

Recently, products composed of styrene, acrylonitrile, and maleic anhydride have been introduced as improvements over the older ABS materials. These products exhibit superior heat resistance and thermal stability in comparison to conventional ABS materials. In addition, the impact resistance of styrene-acrylonitrile-maleic anhydride terpolymers can be improved by the addition of or by grafting onto appropriate elastomers. The product also exhibits desirable rheological behavior due to polar interaction of anhydride groups during processing and drawing. 

Acrylonitrile-styrene-acrylate terpolymers, known as either ASA or AAS, constitute another class of ABS resins, viz. Centrex , Luran S, Richform , etc. These materials may also contain reactive groups, viz. maleic anhydride or glycidyl methacrylate. 

HIPS) is produced commercially by the emulsion polymerization of styrene monomer containing dispersed particles of polybutadiene or styrene-butadiene (SBR) latex. The resulting product consists of a glassy polystyrene matrix in which small domains of polybutadiene are dispersed. The impact strength of HIPS depends on the size, concentration, and distribution of the polybutadiene particles. It is influenced by the stereochemistry of polybutadiene, with low vinyl contents and 36% d5-l,4-polybutadiene providing optimal properties. Copolymers of styrene and maleic anhydride exhibit improved heat distortion temperature, while its copolymer with acrylonitrile, SAN — typically 76% styrene, 24% acrylonitrile — shows enhanced strength and chemical resistance. The improvement in the properties of polystyrene in the form of acrylonitrile-butadiene-styrene terpolymer (ABS) is discussed in Section VILA. 

ABS acrylonitrile-butadiene-styrene copolymer, Terpolymer styrene-acrylonitrile-maleic anhydride copolymer, and MA mole% of maleic anhydride in the terpolymer. 

Thus, workers at Hewlett Packard [13] using this technique identified six volatiles in styrene-acrylonitrile-maleic anhydride terpolymer (benzene, toluene, ethylbenzene, styrene, aromatics, and maleic anhydride). 

A Monsanto patent by Lavengood [38] reported on the free radical copolymerization of styrene (S), acrylonitrile (AN) and maleic anhydride (MA) and the use of these terpolymers in the reactive compatibilization of PA6/ABS blends. Indeed, the amine end groups of nylon react with the MA groups of the terpolymer with formation of a graft copolymer at the interface. 

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