Preparation Of Transparent ABS Resin And Investigation On The Structure And Property

The stiffness and toughness of polymer materials are two important factors for their practical applications. Hence, investigation on the modification of plastics is a focus of polymer material science. ABS resin is one of the important engineering plastic extensively used in the world. Transparent ABS resin has not only general ABS resin mechanical properties, but also good transparency. Investigation on the preparation method of transparent ABS resin has important academic and applied values. Core-shell modifiers can act as impact modifiers to toughen the transparent ABS resin and improve their notched impact strength and transmittance.The advantage of Core-shell modifiers is that the particle size of core-shell modifiers has been set during their synthesis and kept constant when they are blended with matrix resins. In our study, the core-shell modifier, including acrylonitrile-butadiene-styrene and methyl methacrylate-butadiene-styrene copolymers were synthesized by seed emulsion polymerization methods, and these copolymers were used to tough transparent ABS resin. The main research work and conclusions are as follows:1. Polybutadiene (PB) and Styrene-Butadiene(SBR) latex rubbers were synthesized by emulsion polymerization. Methylmethacrylate-styrene(MS) resin,methylmethacrylate-styrene-acrylonitrile (MSAN) resin were prepared by suspension polymerization. Then a series of poly Acrylonitrile-Butadiene-Styrene (ABS) and poly Methyl-methacrylate-Butadiene-Styrene (MBS) were successfully synthesized by grafting Acrylonitrile-styrene copolymer (SAN) onto Polybutadiene latex rubber particles or by grafting styrene and methylmethacrylate monomer onto Styrene-Butadiene latex rubber particles with seeded emulsion polymerization techniques. Transparent Acrylonitrile-Butadiene-Styrene (ABS) resin with good properties was prepared by blending core-shell modifiers with matrix.2. Styrene-acrylonitrile copolymer (SAN) and a-methylstyrene-acrylonitrile copolymer (a-MSAN) with different components was synthesized by emulsion polymerization. Then, PMMA/SAN blend and PMMA/a-MSAN blend were prepared by blending SAN or a-MSAN with PMMA resin. The miscibility of PMMA/SAN blend and PMMA/a-MSAN blend was investigated. The result indicated PMMA and SAN was a immiscible system when St/AN was 50/50,65/35,95/5 in styrene-acrylonitrile copolymer (SAN).However, PMMA and SAN was a miscible system when St/AN was 75/25 in styrene-acrylonitrile copolymer (SAN). PMMA/a-MSAN blend, in which a-MSt partly substituted St, was a miscible system when the content of AN in a-MSAN was 15-25%. PMMA/a-MSAN blend, in which a-MSt substituted St, was also a miscible system when the content of AN in a-MSAN was 15-25%.The influence of the content of a-MSt in a-MSAN on the miscibility of PMMA/a-MSAN blend was investigated. PMMA and a-MSAN was a miscible system in entire composition when the content of AN in a-MSAN was 25%.3. MBS core-shell particles with different structure synthesized by seed emulsion polymerization were used as impact modifier of PMMA/SAN. Results showed that MBS effectively toughened PMMA/SAN in the range of the appropriate sizes. PMMA/SAN/MBS blend had the higher transmittance and the lower haze. MBS effectively toughened PMMA/SAN in the range of the appropriate gel content. PMMA/SAN/MBS blend had the higher transmittance and the lower haze. With the increase of St content arranged in the core of MBS, the impact strength and the transmittance of PMMA/SAN/MBS blend increased and then decreased, the haze of PMMA/SAN/MBS blend decreased and then increased. When St was grafted onto the PB rubber, the resistance of the blend was improved. When St was copolymerized with butadiene in MBS, the optical property of the blend was improved. Compare with PMMA/SAN/SBR-g-SAN blend, PMMA/SAN/PB-g-SAN blend had the higher impact strength and better optical property.4. Poly butyl acrylate, butyl acrylate-styrene copolymer and Butadiene-styrene-butyl acrylate copolymer were synthesized by emulsion polymerization. MABS core-shell modifier was prepared with emulsion grafting polymerization. The kinetics of polymerization and toughening PMMA by MABS core-shell modifier were investigated. Results indicated that copolymer particle size and converse rate increased as solid content increased in the polymerization. The impact strength of PMMA/MABS blend decreased, the transmittance of PMMA/MABS blend increased and then decreased and the haze of PMMA/MABS blend decreased and then increased with the increase of the content of butyl acrylate in core of MABS. The impact strength of PMMA/MABS blend decreased and then increased and got to the maximum value when the particle is 269nm, the transmittance of PMMA/MABS blend increased and then invaried and the haze of PMMA/MABS blend decreased and then invaried with the increase of the particle size of butyl acrylate in core of MABS. It is found that from TEM MABS modifier dispersed in PMMA, which is consistence with the property of PMMA/MABS blend.