Polyblends methyl methacrylate

Heterogeneity, as in polyblends, has also been observed in random copolymers. F. Kollinsky and G. Markert found phase separation in binary mixtures of copolymers of methyl methacrylate and butyl acrylate. C. Kraus and K. W. Rollmann discovered heterogeneity in blends of random copolymers of butadiene and styrene if they differ by more than 20% in composition. 

Elastomeric graft copolymers of methyl methacrylate upon diene and acrylic rubbers were prepared by R. G. Bauer and co-workers. These elastomers are compatible with rigid methyl methacrylate-styrene copolymers of identical refractive index, yielding transparent polyblends. 

The importance of the graft handle on a 62/38 butadiene-methyl methacrylate rubber can be illustrated by its effect on the optical properties of the polyblend. From Table II it can be seen that the reduction in percent haze is dramatic for an increase of methyl methacrylate graft from 0 to 27% by weight, while there is no apparent change in the light transmission. The blend resin in this polyblend system was an 88-12 methyl methacrylate-styrene copolymer, and the total resin to backbone rubber ratio was kept at 2.5-1.0. The measured refractive indices are included for each component (the graft rubber and the blend resin). The difference in refractive index amounts to no more than 0.004 unit for any of the components. 

Typical mechanical properties for transparent injection-molded polymers, designated MBAS, having a compositional range of from 11-18%, 1,3-butadiene, 34-39% styrene, and 23-25% each of acrylonitrile and methyl methacrylate are given in Table IV. This polymer is closely akin to the polyblend described previously, differing by containing a butadiene-styrene elastomer backbone, with a terpolymer resin graft consist-... 

Typical physical properties for an injection-molded transparent acrylic polyblend resin are given in Table II. The injection molding conditions used are given in Table III. Tensile, flexural, and impact properties are within the range reported for typical ABS and high impact polystyrene resins. Optical properties approach those of the acrylics [i.e., poly (methyl methacrylate)]. The strength properties are on the low side of those reported in the first paper for the transparent diene... 

Homogeneous single-phase polyblends are very rare. Liquid-liquid phase separation of optically homogeneous polyblends of a styrene/acrylonitrile copolymer with poly (methyl methacrylate) has been studied by L. P. McMaster. A quantitative test method of the dynamic mechanical properties of multiphase polymer systems was developed by L. Bohn. He was able to demonstrate the correlation between shear modulus and gel volume of brittle polymers... 

Polyblends in which both phases are rigid are frequently called poly alloys. Poly (phenyl oxide) is blended with impact polystyrene to improve melt flow. Complete compatibility between the two phases is rare and was observed between poly (methyl methacrylate) and poly(vinylidene fluoride) by D. R. Paul and J. O. Altamirano. Thermoplastics are added to polyesters to reduce mold shrinkage. 

On the basis of a systematic study of the emulsifying effect of block copolymers in PS-PI and in polystyrene-poly (methyl methacrylate) (PS-PMM) polyblends (3), it was possible to represent schematically the appearance of the films for different blend compositions as functions of molecular weight and composition of the block copolymer (Cop), as well as of molecular weight of the homopolymers (see Figure 2). Thus in a polyblend containing PS and PI of practically the same molecular weight — M2), the best... 

Similar trends were noted on polyblend formation of PVC with various methacrylates and acrylates when PVC was blended with poly(methyl methacrylate) (PMMA), poly(ethyl methacrylate) (PEMA), poly(bntyl methacrylate) (PBMA), poly(ethyl acrylate) (PEA) and poly(butyl acrylate) (PBA) (Chakrabarti and Chakraborty, 2006 Chakrabarti and Chakraborty, 2007). The blends were characterized with respect to their physicomechanical, thermomechanical, thermal and morphological properties. The blends were prepared with PVC and the different methacrylates and acrylates in varying composition ratios of each polymer. The me-... 

They observed that protonated emeraldine using these dopants has a good solubility in cresol, which is a excellent solvent for many classical polymers such as poly(methyl methacrylate). This methodology of using a dopant having a surfactant group led to the preparation of polyblends with following polymers. Nylon, polycarbonate, polystyrene, polysultone, poly(-vinylacetate) polypropylene, poly(vinylchloride), acrylonitrile butadiene-styrene copolymer (ABS) and poly methyl (methacrylate). 

Singh, Y.P. and Singh, R.P. (1983) Compatibility studies on solid polyblends of poly(methyl methacrylate) with poly (vinyl acetate) and polystyrene by ultrasonic technique. J. Eur. Polym., 19, 529-533. 

The polyblends show differences amongst themselves. Acrylonitrile-butadiene-styrene (ABS) polyblend is more sensitive to thermal oxidation than methyl methacrylate-butadiene-styrene (MBS) polyblend or methyl methacrylate-acrylonitrile-butadiene-styrene (MABS) polyblend. Consequently, processed ABS photo-oxidises with little or no induction period. 

The degradation behaviour of a number of graft copolymers prepared by mastication of PVC in presence of another monomer has been studied. Graft copolymers of PVC were so produced using methyl, ethyl and heptyl methacrylate respectively and also with a styrene or styrene/MMA mixture. Again the effect of the higher dispersion is to enhance the interaction effects e.g. methacrylate monomer production, PS fall in MW) observed in the corresponding polyblends. 

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