Reactive compatibilization was used to control and stabilize 20-30 wt% poly(dimethylsiloxane) (PDMS) dispersions in nylon 6 (PA6) and poly(styrene) (PS), respectively. The effect of the type of reaction (amine (NH,)/anhydride (An), NH,/ epoxy (E) and carboxylic acid (COOH)/E) on the morphology was studied with electron microscopy. PS and PDMS have mutual solvents and thus it was possible to use gel permeation chromatography (GPC) to determine the concentration of block copolymer in PS/PDMS blends. Reactive blending of PA6 with difunctional PDMS-(An], did not decrease the PDMS particle size compared to the non-reactive blend (-10 pm). Particle size decreased significantly to about 0.5 pm when PA6 was blended with a PDMS containing about 4 random An groups along the chain. For the PS/PDMS blends, GPC revealed that the NH2/An reaction formed about 3940 block copolymer and produced stable PDMS particles -0.4 pm. No reaction was detected for the PS-NH,/PDMS-E blend and the morphology was coarse and unstable. Also, PS-NH,/PDMS-An reactivity was lower compared to other systems such as PS/poly(isoprene) and PS/poly(methylmethauylate) using the same reaction. This was attributed to the relatively thinner PS/PDMS interface due to the high PS/PDMS immiscibility.

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This paper reports about the polymerization of -caprolactam monomer in the presence of low molecular weight hydroxyl or isocyanate end-capped ethylene-butylene elastomer (EB) elastomers as a new concept for the development of a submicron phase morphology in polyamide 6 (PA6)/EB blends. The phase morphology, viscoelastic behavior, and impact strength of the polymerizationdesigned blends are compared to those of similar blends prepared via melt-extrusion of PA6 homopolymer and EB elastomer. Polyamide 6 and EB elastomer were compatibilized using a premade triblock copolymer PA6-b-EB-b-PA6 or a pure EB-b-PA6 diblock reactively generated during melt-blending (extrusion-prepared blends) or built-up via anionic polymerization of -caprolactam on initiating -NCO groups attached to EB chain ends (polymerization-prepared blends). Two compatibilization approaches were considered for the polymerization-prepared blends: (i) the addition of a premade PA6-b-EB-b-PA6 triblock copolymer to the -caprolactam monomer containing nonreactive EB-OH elastomer and (ii) generation in situ of a PA6-b-EB diblock using EB-NCO precursor on which polyamide 6 blocks are builtup via anionic polymerization of -caprolactam. The noncompatibilized blends exhibit a coarse phase morphology, either in the extruded or the polymerization prepared blends. Addition of premade triblock copolymer (PA6-b-EBb-PA6) to a EB-OH /-caprolactam dispersion led to a fine EB phase (0.14 m) in the PA6 matrix after -caprolactam polymerization. The average particle size of the in situ reactively compatibilized polymerization-prepared blend is about 1 m. The notched Izod impact strength of the blend compatibilized with premade triblock copolymer was much higher than that of the neat PA6, the noncompatibilized, and the in situ reactively compatibilized polymerization blends.

In this work, biodegradable properties of gelatin and polyethylene compositions, in addition to, influence of ultra violet radiation and peroxide groups were studied. In order to obtain thermoplastic gelatin water and glycerin were used as a plasticizer. For polyethylene/gelatin blends, to provide compatibility polyethylene functionalized with maleic anhydride. It was found that as gelatin content increases, biodegradation also grows while mechanical properties (elastic module and yield strength) decrease.