Preparation method of intercalated and modified organic montmorillonite composite foaming agent for polyvinyl chloride

Abstract

The invention discloses a preparation method of an intercalated and modified organic montmorillonite composite foaming agent for polyvinyl chloride. The method comprises the steps of firstly carrying out organic modification on montmorillonite by using benzyl triphenyl phosphonium chloride; secondly carrying out intercalation on the modified montmorillonite by using azodicarbonamide and achieving uniform dispersion of the azodicarbonamide between montmorillonite laminates through control of a series of technological conditions; and finally further reducing the decomposition temperature of the foaming agent through coordinating with addition of a proper amount of zinc oxide and sodium bicarbonate, adding the foaming agent to polyvinyl chloride, thereby avoiding the phenomenon of pasting of the polyvinyl chloride. Industrial control is facilitated by a synthetic process of a product produced by the process, the production cost is reduced, the foaming temperature is moderate, the product is very suitable for a foaming process of the polyvinyl chloride and is not decomposed or pasted in the foaming process, a foaming material formed by the foaming agent is stable in quality, dense and uniform in cells and excellent in heat preservation effect, and has a certain flame-retarding effect.

Description

technical field [0001] The invention relates to the technical field of foamed polyvinyl chloride, in particular to a preparation method of an intercalated modified organic montmorillonite composite foaming agent for polyvinyl chloride. Background technique [0002] In recent years, the domestic and foreign foam plastic industry has developed rapidly, and its application scope has become more and more extensive, especially in packaging, construction, transportation, cable materials and other industries, foam plastic has become an irreplaceable material. Polyvinyl chloride foam material has superior toughness and thermal insulation performance, low material cost, excellent flame retardancy, and has an irreplaceable position in the field of foam plastics. The polyvinyl chloride foaming process generally uses chemical foaming, most of which use azodicarbonamide, commonly known as AC foaming agent, or OBSH foaming agent (4,4-oxobisbenzenesulfonyl hydrazide. However, the two foams...

AI Technical Summary

Problems solved by technology

But both foaming agents have two problems: (1) The decomposition temperature is relatively high, the decomposition temperature of AC is between 190-220°C, and the decomposition temperature of OBSH is in the range of 150-160°C

When AC and OBSH are used as foaming agents to add to the base material for foaming, there will be problems such as the decomposition temperature is too high and the softening temperature of PVC does not match, and the foaming material is easy to age and turn yellow; (2) It is easy to absorb air Agglomeration of the moisture in the foam will cause the foaming material to have excessive local foaming agent content, concentrated foaming, cell rupture, and foaming.

Polyvinyl chloride material is very easy to decompose when heated, easy to paste, unstable, and it is impossible to simply use these two commonly used chemical foaming agents