TH14581B - The process for preparing thermoplastic resin expansion products - Google Patents

Abstract

DC60 (23/07/40) The process for preparing the thermoplastic resin expansion products revealed here, which consists of a gas dissolution process of carbon dioxide and / or nitrogen, is supercritical. The foaming agent is deposited into the thermoplastic resin, and melted in the thermoplastic resin, a cooling process. Of cooling the molten resin component under pressure not less than the critical pressure of the foaming agent, the nucleus formation process of releasing the molten resin component from the diene 4 to reduce the pressure. To a level that is not greater than critical pressure, and the expansion control process of making expansion products The thermoplastic resin is cooled to a level not greater than the glass transition temperature. Or temperature The resin crystals are formed to control the cell diameter of the expanded product, whereby the It consists of a shear rate modifier 12 with shear rate generation function in the range of 10 to a power of 2 to a power of 4 s -1 and a cross-sectional area A, and a flow velocity distribution modifier 13, and With cross-sectional areas B, and B / A in the range of 1.3 to 20, where cell diameter and cell density are controlled through this process, expansion products of the thermoplastic resin with Surface characteristics Excellent exterior, high strength, fine cell average diameter and cell density. And where carbon dioxide and / or nitrogen are used as foaming agents The process for preparing the thermoplastic resin expansion products disclosed here, which consists of gas dissolution steps of carbon dioxide and / or nitrogen, is supercritical. The foaming agent is deposited into the thermoplastic resin, and melted in the thermoplastic resin, a cooling process. Of cooling the molten resin component under pressure not less than the critical pressure of the foaming agent, the nucleus formation process of releasing the molten resin component from the diene 4 to reduce the pressure. To a level that is not greater than critical pressure, and the expansion control process of making expansion products The thermoplastic resin is cooled to a level not greater than the glass transition temperature. Or temperature The resin crystals are formed to control the cell diameter of the expanded product, whereby the It consists of a shear rate modifier 12 with a shear rate generation function in the range of 102 to 104 s -1 and a cross-sectional area A, and a flow velocity distribution modifier 13 and a cross-sectional area B, And B / A is in the range of 1.3 to 20, where cell diameter and cell density are controlled through this process, an expansion product of thermoplastic resin with a textured surface can be obtained. Excellent exterior, high strength, fine cell average diameter and cell density. And where carbon dioxide and / or nitrogen are used as foaming agents

Claims (1)

1. The process for preparing thermoplastic resin expansion products by Extrusion includes: (I) a gas melting process of a thermoplastic resin at 100 to 450 ° C in a continuous plasticizer with a foaming agent, and a Filled with carbon dioxide And / or supercritical nitrogen at a ratio of 0.1 to 30 parts by weight versus 100 parts by thermo-weight. Plastic resin to form a molten resin component, which thermoplastic Resins are compatible with carbon dioxide. And / or supercritical nitrogen (II) coolant process of cooling the molten resin component to a temperature of 50 to 300 ° C at the end of a continuous plasticizer, while keeping the pressure low. Over the critical pressure of carbon dioxide and / or supercritical nitrogen (III), the nucleic acid formation of the molten resin component. Discharge from the kyine connected to the end of the plasticizer, continuous and set The optimal expansion temperature of the molten resin component, where the pressure is reduced to a level not greater than the carbon dioxide critical pressure and / or supercritical nitrogen to form nuclei cells, and (IV ) The process of controlling the expansion of thermoplastic extrusion products The plastic resin cools rapidly to a level not greater than the glass transition temperature or the resin crystallization temperature to control its diameter. Of the cell of the product is enlarged, where the dyne in step (III) modulates the Distribution velocity of flow With the function of reducing the upper shear rate The next side of the shear adjustment section With the function of generating rates Shear in the molten resin component (Hereinafter referred to as simply "shear rate") in the range of 10 2 to 10 4 s -1; This shear rate modifier includes the section (mean cross-sectional area A) in which the cross-sectional area of the part is perpendicular to the direction of Resin flow on the previous side of the resin flow path is narrowed; Flow velocity distribution adjustment section, including section (Mean cross-sectional area B) in which the same section is spread on later sides of the flow path; And B / A ranges from 1.3 to 20. 2. The process for preparing thermoplastic resin-based expansion products. Claim No. 1, where Diene has the function of changing the cross-sectional area of the shear rate modifier 3. The process for the preparation of thermoplastic resin-based expansion products. Claim 1, where the resin pressure at the inlet of the shear rate modifier ranges from 50 to 400 kg / cm 2 4. Process for preparing thermoplastic resin-based expansion products. Claim 1, in which the C / A ratio between the mean cross-sectional area A of the shear modifier and the cross-sectional area C of the thermoplastic resin expansion products obtained ranges from 2 to 200 5. The process for Preparation of thermoplastic resin-based expansion products Claim 1, where the continuous plasticizer is a co-rotating extruder 6. Process for preparing thermoplastic resin-based expansion products. Claim No. 1, where the continuous plasticizer is an extruder 7. Process for preparing thermoplastic resin-based expansion products. Claim 1, which carbon dioxide And / or nitrogen was dissolved in the thermoplastic resin at a ratio of 2 to 20 parts by weight versus 100 parts by weight of the thermoplastic resin. 8. Process for preparing thermoplastic expansion products. Resin based Claim 1, in which the molten resin component continues to be composed as a fine inorganic compound and / or aliphatic carboxylic acid derivative. Resin based thermoplastic Claim 8, in which fine inorganic powder is talc 1 0. Process for preparing thermoplastic resin-based expansion products. Claim 8, where aliphatic carbon silicic acid derivatives are stearic acid derivatives 1 1. A process for preparing thermoplastic resin-based expansion products. Claim 10, where the derivative of aliphatic carboxylic acid is zinc stearate.