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CN-119978514-B - PVC foaming regulator and preparation process thereof

CN119978514BCN 119978514 BCN119978514 BCN 119978514BCN-119978514-B

Abstract

The application belongs to the technical field of PVC foaming agents, and particularly provides a PVC foaming regulator and a preparation process thereof, wherein the preparation process of the PVC foaming regulator comprises the following steps of 1) blending a mixed monomer, an emulsifying agent and water to prepare a pre-emulsion; the mixed monomer comprises MMA and BA, 2) dissolving cyclodextrin derivatives, disaccharides and modified polyethylene glycol in a solvent, then adding maleimide for reaction to prepare a precursor solution, 3) taking pre-emulsion for polymerization reaction, adding the precursor solution into a reaction system when the monomer conversion rate is 70-80%, continuing to react until the internal temperature is reduced, stopping the reaction, then freezing, demulsifying, drying and pulverizing to obtain the modified polyethylene glycol modified cyclodextrin. The PVC foaming regulator prepared by the application has the advantages of moderate intrinsic viscosity and good foaming effect.

Inventors

  • LIU YANYAN
  • WANG JIAFU
  • LIU SHENG
  • WU DEFENG
  • WANG YONGXU
  • ZHANG KUN

Assignees

  • 山东和天下新材料有限公司

Dates

Publication Date
20260512
Application Date
20250414

Claims (6)

  1. 1. A preparation process of a PVC foaming regulator is characterized by comprising the following steps: 1) Blending a mixed monomer, an emulsifying agent and water to prepare a pre-emulsion, wherein the mixed monomer comprises MMA and BA; 2) Dissolving cyclodextrin derivative, disaccharide and amine-terminated polyethylene glycol in a solvent, then adding maleimide for reaction to obtain a precursor solution, wherein the mass ratio of the cyclodextrin derivative to the disaccharide to the amine-terminated polyethylene glycol is 1 (0.1-0.15) (0.3-0.5), the cyclodextrin derivative is prepared by adopting the method comprising the following steps of S1, dissolving cyclodextrin and sodium hydroxide in deionized water, then adding ethanol solution of p-toluenesulfonyl imidazole for reaction to obtain an intermediate product; 3) And (3) taking the pre-emulsion for polymerization reaction, adding a precursor solution into a reaction system when the monomer conversion rate is 70-80%, wherein the volume ratio of the pre-emulsion to the precursor solution is 1 (0.15-0.2), continuing the reaction until the internal temperature is reduced, stopping the reaction, adding 3-aminophenylboric acid and bis (trifluoromethyl) sulfonyl imide, wherein the addition of the 3-aminophenylboric acid is 2-3% of the mass of the pre-emulsion, the addition of the bis (trifluoromethyl) sulfonyl imide is 0.5-1% of the mass of the pre-emulsion, and then performing freeze demulsification, drying and pulverization to obtain the modified epoxy resin.
  2. 2. The process for preparing the PVC foaming modifier according to claim 1, wherein in the step 1), the mixed monomer consists of MMA and BA according to a mass ratio of (9-13) to 1; and/or, in the step 1), the emulsifier is one of sodium dodecyl sulfate, sodium dodecyl benzene sulfonate, sodium dodecyl aminopropionate and cetyltrimethylammonium bromide; And/or, in the step 1), the mass of the emulsifier accounts for 3-5wt% of the mass of the mixed monomers.
  3. 3. The process for preparing a PVC foam regulator according to claim 1, wherein in the step 2), the disaccharide is one or more of lactose, trehalose and maltose.
  4. 4. The process for preparing a PVC foam regulator according to claim 1, wherein in the step S1, the molar ratio of cyclodextrin to p-toluenesulfonyl imidazole is 1 (1.2-1.5).
  5. 5. The process for preparing a PVC foam regulator according to claim 1, wherein in the step S2, the molar ratio of cyclodextrin to N-vinylimidazole is controlled to be 1 (1.5-2).
  6. 6. A PVC foam regulator, characterized in that the PVC foam regulator is prepared by the preparation process as claimed in any one of claims 1 to 5.

Description

PVC foaming regulator and preparation process thereof Technical Field The application belongs to the technical field of PVC foaming agents, and particularly relates to a PVC foaming regulator and a preparation process thereof. Background The PVC foaming product has the characteristics of water resistance, flame retardance, acid and alkali resistance, moth resistance, light weight, heat preservation, sound insulation and shock absorption, is an ideal substitute for wood, aluminum and composite boards, is widely applied to various fields such as boards for interior decoration, external wall boards for buildings, boards for interior decoration, offices, houses, buildings in public places and the like, and has very important application value. With the development of PVC material technology, the performance requirements of people on PVC foaming products are higher and higher, and meanwhile, the problems of poor foam impact resistance, long foam processing period, low processing efficiency and the like occur in the application process of the PVC foaming products. For this reason, it is required to improve the foaming performance of the foamed article to solve the above-mentioned problems. In the PVC foaming process, the acrylic ester foaming regulator has the effects of improving the processability of PVC, promoting the plasticizing performance of PVC, adjusting the pore structure of bubbles generated in the foaming process and improving the strength of PVC foaming melt, so that a large number of bubbles can be prevented from being combined, and the PVC foaming melt foaming agent has great help to obtain uniformly foamed PVC products. The foaming regulator of acrylic ester is one kind of acrylic ester multipolymer with superhigh molecular weight and multilayer structure, and its chemical composition is obtained through multistage emulsion polymerization of acrylic ester monomer and other monomer. For example, patent application publication number CN117757129a discloses a PVC foam regulator and a preparation method thereof, the regulator is formed by dewatering and drying a polymerization emulsion, the polymerization emulsion is formed by mixing and blending an acrylic ester compound, a methacrylic ester compound, a pH regulator, an initiator and the like, and the PVC foam regulator is prepared by copolymerizing a plurality of compounds, so that the intrinsic viscosity of the obtained copolymer is higher than that of a copolymer obtained by a single-initiation system. As another example, the patent application document with the application publication number CN112940168a discloses a production process of a high-viscosity PVC foaming regulator, by changing the initiation mode and adopting a redox compound initiation system, the reaction is accelerated, thereby improving the reaction rate, increasing the molecular weight of the polymer, and by controlling the usage amount and reaction condition of each raw material component, the emulsion polymerization is enabled to react at a lower initiation temperature and with a smaller usage amount of initiator to obtain a copolymer with a larger molecular weight, and the intrinsic viscosity of the PVC foaming regulator is improved. Molecular weight is an important indicator for acrylate foam regulators. Along with the improvement of the molecular weight of the acrylic ester foaming regulator, the foaming regulator can play a good role in stabilizing and enhancing foams in the foaming process. However, after the dosage and the molecular weight of the acrylic foaming regulator reach certain limit values, on one hand, the molecular weight of the acrylic foaming regulator is too large, the synthesis difficulty and the cost are higher, and on the other hand, the viscosity is too high due to the too large molecular weight, and the control of the foaming process is also adversely affected, so that how to improve the foaming effect of PVC within a certain molecular weight range is a technical problem to be solved urgently. Disclosure of Invention Aiming at the problems, the application provides a PVC foaming regulator and a preparation process thereof in order to further improve the performance of the acrylic foaming regulator. The application firstly provides a preparation process of a PVC foaming regulator, which comprises the following steps: 1) Blending a mixed monomer, an emulsifying agent and water to prepare a pre-emulsion, wherein the mixed monomer comprises MMA and BA; 2) Dissolving cyclodextrin derivatives, disaccharides and modified polyethylene glycol in a solvent, and then adding maleimide for reaction to obtain a precursor solution; 3) And (3) taking the pre-emulsion for polymerization reaction, adding a precursor liquid into a reaction system when the monomer conversion rate is 70-80%, continuing to react until the internal temperature is reduced, stopping the reaction, then freezing, demulsification, drying and pulverization. Further, in the step 1), the mixed monome