Method for preparing whitening foaming agent

Abstract

The invention discloses a method for preparing a whitening foaming agent. The method comprises the following steps: S11, stirring and mixing sodium bicarbonate and a composite calcium-zinc stabilizeruniformly; S12, performing air flow crushing so as to obtain a half-finished product A; S21, uniformly mixing citrate and citric acid, and performing air flow crushing; S22, completing coating of fatty acid and derivatives thereof on the citrate and the citric acid so as to obtain a half-finished product B; and S3, preparing the whitening foaming agent, namely mixing the half-finished product A and the half-finished product B, further adding a proper amount of urea and derivatives thereof and epoxy compounds, so as to obtain the whitening foaming agent, wherein the mass ratio of the sodium bicarbonate to the composite calcium-zinc stabilizer is 100:(1-5). The whitening foaming agent prepared by using the method for preparing the whitening foaming agent has a good foaming effect on polyvinyl chloride, moderate in foaming velocity, small in heat in the foaming process and capable of remarkably improving the whiteness, the surface glossiness, the foam pore fineness, and the like of a polyvinyl chloride foaming product.

Description

technical field [0001] The invention relates to the field of foaming agents, in particular to a preparation method of a whitening foaming agent, more particularly to a whitening foaming agent for polyvinyl chloride and a preparation method thereof. Background technique [0002] Polyvinyl chloride (PVC for short) is one of the five general-purpose plastics in the world, among which rigid polyvinyl chloride foam has the characteristics of low density, geothermal conductivity, high chemical stability, and high energy absorption, and is widely used as heat insulation , Noise-reducing and shock-absorbing materials, especially suitable for the production and processing of bathroom cabinet boards, special boards for building templates, special boards for automobiles and ships, special boards for advertising engraving, and special boards for chemical anticorrosion. [0003] Polyvinyl chloride is a chain-like high polymer formed by the homopolymerization of vinyl chloride monomers. I...

AI Technical Summary

Problems solved by technology

[0003] Polyvinyl chloride is a chain-like high polymer formed by the homopolymerization of vinyl chloride monomers. Its decomposition temperature is lower than its glass transition temperature, and it is prone to dehydrochlorination and decomposition, which will cause discoloration of the product, affect the processing performance of polyvinyl chloride and cause mechanical damage to the product. Performance drop

The introduction of ultra-fine high-residue inorganic foaming agent sodium bicarbonate increases the strength of the melt, the fluidity of the melt becomes poor, and the heat generated by internal friction increases. Insulation performance and mechanical properties cause great adverse effects; the introduction of exothermic AC foaming agent (azodicarbonamide) leads to local overheating of PVC melt and scorching and yellowing

[0004] The above problems are prominent in the existing conventional foaming agents, resulting in extremely unstable production quality of downstream product manufacturers, so they have to increase the amount of stabilizers and often shut down for debugging