Carboxylated poly blends

In practice, the existence of both UCST and LCST has been established for polymer-solvent systems. About 10 years ago, Schmitt discussed UCST, LCST and combined UCST and LCST behavior in blends of poly(methyl methacrylate) with poly(styrene-co-acrylonitrile) (PMMA-PSAN), Ueda and Karasz reported the existence of UCST in chlorinated polyethylene (CPE) blends using DSC, Inoue found that elastomer blends of cis-l,4-polybutadiene and poly(styrene-co-butadiene) exhibit both UCST and LCST behavior and Cong et al. (72) observed that blends of polystyrene and carboxylated poly(2,6-dimethyl-l,4-phenylene oxide) copolymers with a degree of carboxylation between molar fraction 8% and 10% exhibit both UCST and LCST behavior. They used DSC to establish the phase diagram. 

Figures 4.49 and 4.50 show the DSC curves at different annealing temperatures and the phase diagram for a blend of polystyrene (M , = 115 000) and carboxylated poly(phenylene oxide) (PPO) with molar fraction 8.0% carboxyla-tion content.

HAR Haraguchi, M., Nakagawa, T., and Nose, T., Miscibihty of associated polymer blend solutions 1. One-end-aminated polystyrene/one-end-carboxylated poly (ethylene glycol) blends in toluene, Polymer, 36, 2567, 1995. 

Carboxylated polyesters were prepared by extending hydroxyl-terminated polyester segments with dianhydrides. Carboxylated polyesters which were soluble in common lacquer solvents were effective in improving the adhesion of coatings on a variety of substrates when 1-10% was blended with cellulose acetate butyrate, poly(vinyl chloride), poly(methyl methacrylate), polystyrene, bisphenol polycarbonates, and other soluble polymers. 

Table II shows the effect of the carboxyl content on the adhesive characteristics of PMDA-extended polyesters in blends with K-l polycarbonate [4,4 - (2-norbomylidene) diphenol polycarbonate] (VIII), cellulose acetate butyrate, and poly (vinyl chloride). K-l polycarbonate is an experimental polymer which, like cellulose acetate butyrate and poly (vinyl chloride), is very sensitive to adhesive changes because only 1-2% of a carboxylated...

T50I(NPG)/PMDA was of particular interest because of its adhesive characteristics, oxidative stability, and polymer cost. Table III shows the improvement in adhesion obtained when various substrates were coated with blends containing this polyester (acid number 39). As indicated in the table, the ease of obtaining adhesion on the different substrates decreased approximately in the following order brass > steel > copper > chrome-coated steel > aluminum > nylon 66 > poly (ethylene terephthalate). In spite of the wide differences in structure and polarity of the various polymers, the carboxylated polyester significantly improved the adhesion of the coatings. 

Li XG, S H, Lai YH, Wee ATS (2000) Miscibility of carboxyl-containing polysilox-ane/poly(vinylpyridine) blends. Polymer 41 6563-6571... 

A conducting, polymeric film of poly(indole-5-carboxylic acid) has been employed for covalent immobilization of tyrosinase, which retains catalytic activity and catalyzes oxidation of catechol to the quinone <2006MI41>. Poly(l-vinylpyrrole), polyfl-vinylindole), and some methyl-substituted compounds of poly(l-vinylindole) are of potential interest as photorefractive materials with a relatively low glass-transition temperature and requiring a lower quantity of plasticizer in the final photorefractive blend <2001MI253>. Polymers of 5,6-dihydroxyindoles fall within the peculiar class of pigments known as eumelanins and their chemistry has been reviewed <2005AHC(89)1>. 

Optical microscopy shows that the phase separation of immiscible polyisoprene and poly(a-methylstyrene) is controlled by the ammonium carboxylate pairs bridging the chain extremities at a level that depends on the ion pair content (i.e. the molecular weight of the blended teleche-... 

Poly(amino acids)2892 and polypeptides2893 can also be grafted onto starch. Starch was first alkylated in the presence of lithium naphthalene, and then the alkoxy derivatives were reacted with /V-carboxy anhydrides. Poly(amide amines) were produced by reacting amines with dioic acids on starch and then crosslinking with epichlorohydrin or 1,2-dichloroethane 2894 Grafting of starch with a synthetic polymer chain, for instance, polystyryl carboxylate anions prepared by an anionic polymerization, can be carried out on a blend of starch and cellulose functionalized by sulfonation, mesylation, or tosylation. In this manner, cellulose-starch graft copolymers were prepared.2895... 

BR and/or poly(ethylene-co- vinyl or acrylic monomer), e.g., EVAc EPDM polynorbornene having carboxylic, and carboxylic ester groups PVC blends with crosslinked NBR for foamed floating devices DOIP plasticized PVC blended with TPU and EVAc... 

Reactive compatibilizing agents of the type A-C can also compatibilize an A/B blend as long as C can chemically react with B. Such studied systems include polyethylene (PE)/nylon-6 blends compatibilized with carboxyl functional PE, polypropylene (PP)/poly(ethylene-terephthalate), with PP-g-acrylic acid, nylon-6,6/EPDM with poly(styrene-co-maleic anhydride), and nylon-6/PP with PP-g-maleic anhydride. 

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