Abstract: The present application relates to a membrane separation device. According to the separation device of the present application, components to be separated using a separation membrane having a small area size can be separated with high selectivity and consequently processing efficiency and economical efficiency can be superbly improved; and according to a method for producing an expanded polystyrene which includes the membrane separation device, components to be separated using a separation membrane having a small area size, in particular, a volatile organic compound (VOC), can be separated with high selectivity and consequently processing efficiency and economical efficiency can be superbly improved, and also, by separating and recovering VOC, an effect in preventing environmental pollution caused by global warming is exhibited.

Abstract: The present application relates to a membrane separation device. According to the separation device of the present application, components to be separated using a separation membrane having a small area size can be separated with high selectivity and consequently processing efficiency and economical efficiency can be superbly improved; and according to a method for producing an expanded polystyrene which includes the membrane separation device, components to be separated using a separation membrane having a small area size, in particular, a volatile organic compound (VOC), can be separated with high selectivity and consequently processing efficiency and economical efficiency can be superbly improved, and also, by separating and recovering VOC, an effect in preventing environmental pollution caused by global warming is exhibited.

Abstract: The present invention provides a method for manufacturing the imide-substituted polymer comprising the following four consecutive steps of (i) the copolymerization step of copolymerizing aromatic vinyl monomers and unsaturated dicarboxylic anhydride monomers, (ii) the separation step of removing the unreacted monomers and solvents from the abovementioned copolymerized solution continuously supplied to the separator, (iii) the imide substitution step of reacting unsaturated dicarboxylic anhydride units in said copolymers with primary amines, and (iv) the devolatilization step of removing low-molecular-weight volatiles from the polymer solution. The imide-substituted polymer manufactured according to the methods in the present invention has greatly improved the heat resistance and the productivity as the content of aromatic vinyl homopolymers is reduced significantly and the reaction time is shortened extensively.

Abstract: The present invention relates to a method for preparing an imide substituted copolymer resin comprising the steps of: copolymerization by feeding a mixture of an aromatic vinyl monomer and a vinyl cyanide monomer, a mixture of an unsaturated dicarboxylic anhydride monomer and a solvent, an initiator and a chain transfer agent at once to a copolymerization reactor; and imide substitution by continuously feeding the resultant polymerization solution to an imide substitution reactor while continuously feeding a primary amine. The preparation method according to the present invention is capable of continuously preparing an imide substituted copolymer resin having superior heat resistance and excellent fluidity and improving mechanical property and compatibility with ABS resin by inhibiting formation of aromatic vinyl homopolymer.