Recent Advances in Poly meth acrylate Based Blends and Composites

7 Recent Advances in Poly(meth)acrylate Based Blends and Composites 

Copolymerization with other vinyl monomers, such as St and VAc, allows for further modification of acrylic and methacrylic esters. The ease of structural modification to produce desired blend properties (miscibility) is well-documented in the experimental literature. The common methacrylate polymer is PMMA and has been noted to be miscible with various other polymers such as PVC and PEO. 

The majority of compositionally different poly(meth)acrylates are immiscible. Nevertheless, there are some examples noted in the literature of miscible combinations. One of the most interesting and well-studied cases involves isotactic PMMA (iPMMA) with syndiotactic PMMA (sPMMA).[149] The miscibility observed may be expected, but the formation of a stereocomplex offered an interesting system to study. The tacticity of PMMA blends with poly(vinyl pyrrolidone) (PVP) affected the blend phase behavior as atatic and syndiotactic PMMA were miscible with PVP, but isotactic PMMA was phase sepa-rated.[150,151] Miscibility with upper critical solution temperature (UCST) behavior was observed for PnBA blends with poly(propylene glycol) (linear and three arm star) oligomers.[152] Poly(vinyl buty-ral)/PMMA blends were found to be phase separated at high MW PMMA.[153] At low MW PMMA (2000-5000 g/mol), miscibility with UCST behavior was observed. The PMAA/PVAc miscibility was 

The miscibility between several (meth)acrylate polymers and phenoxy (PHE) has been reported.[155,156] PEMA was noted to be partially miscible and PBMA to be phase separated in PHE blends. [155] An investigation of the effect of PMMA s tacticity on the phase behavior of PMMA/PHE blends showed aPMMA, sPMMA and iPMMA to all exhibit miscibility with PHE. [156] The miscibility of PMMA with a vinylidene chloride-acrylonitrile (20 wt% AN) copolymer was shown to be a function of the PMMA tacticity (aPMMA and iPMMA miscible with the copolymer and sPMMA immiscible). [157] Hsu et fl/.[158] reported the effect of tacticity of PMMA on the miscibility with PVAc. This study showed a limited effect of tacticity and solvent choice on the phase behavior of PMMA/PVAc blends and all blends were analyzed as being immiscible based on the observation of two Tgs. Modest areas of miscibility were established for MA, EA, nBA, and 2-ethylhexyl acrylate based acrylate-acrylic acid in the respective copolymers. No miscible combinations were found for MMA-AA or acrylate-MAA copolymers with vinyl acetateethylene (VAE) or PVAc. 

Polyfvinyl methyl ether) (PVME) was known to exhibit marginal miscibility with poly(benzyl methacrylate) with LCST behavior. [159] This blend is found to offer distinct similarities to PS/PVME blends. Immiscibility of PVME with a host of other poly(meth) acrylates was observed.[159] PMMA has been shown to be miscible with poly(3-hydroxybutyrate) (PHB) a naturally occurring polyester that can be produced by bacterial fermentation, which has been commercialized as a biodegradable polymer.[160] 

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