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The topics to the twin screw as the main reaction vessel, the liquid carbon dioxide and ethylene oxide copolymer oligomer (Mn = 2000) reactive extrusion, the use of a chain extender, diisocyanate and coupling agent, a chain extender enhanced by study mechanical structure, machining process and formula composition, so that a liquid oligomer reaction to become a film material with blow molding performance. The research copolymer of carbon dioxide and propylene oxide as the main raw material, both solidified carbon dioxide with the advantages of self-degradation, in the current context of the world's climate and energy, the prospects are very bright. But is currently subject to a large amount of catalyst and synthesis of harsh environment sided factors, the cost of synthesis of the copolymer is very high, and production capability is not high. At the same time, due to the structure of the material itself, brittle and heat resistance are very poor, poor processing performance. This topic in a twin screw extruder as a plug flow reactor, reactive extrusion of low molecular weight copolymer prepolymer chain extender, and then by coupling agent further processing, the material to achieve low-cost and continuous production , while improving the processing performance of the material. The entire process of this experiment are adhered to the principle of \The experimental procedure to a twin-screw extruder for the reaction vessel of carbon dioxide and propylene oxide copolymer, isocyanate ester (MDI) and the chain extender is 1,4 - butanediol (BDO) chain extender, reactive extrusion, and further using a single screw extruder out of the machine, with the coupling agent copolymer processing to further improve its mechanical properties. Universal material testing machine and melt index instrument study under different formulations and processes copolymer of mechanical properties and melt index changes, results showed that, the isocyanate index, the expansion amount of the chain extender, screw reactive segment temperature and screw speed, is impact copolymerization Mechanical Properties of the main factors. Comprehensive consideration, when the isocyanate index R is 1.3, the p value of 0.6 for the chain extender, the reaction temperature was 120 ° C and for a twin-screw, the screw speed 30r/min, coupling agent 0.2% BASF4368CS, reactive extrusion of the copolymer reaches the blow Plastic requirements. Infrared Characterization tests show that occurred within the twin screw extruder chain extension reaction, a molecular weight of the various stages of the reaction was observed by GPC, the molecular weight of the reactants by reactive extrusion was increased from 2000 to 2 × 104, and through the coupling treatment, to improve the mechanical properties and dimensional stability.
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