Several methods to improve the heat resistance of PVC

Several methods to improve the heat resistance of PVC

Several methods to improve the heat resistance of PVC

1 VC copolymer

If the composition of VC (vinyl chloride) and other monomer copolymer resins contains polar or large group components, the thermal deformation temperature of the copolymer increases accordingly, and the heat resistance is better than that of PVC. The softening temperature of PVC is 78 ℃, while the softening temperatures of copolymers vinyl chloride vinylidene chloride, vinyl chloride methyl methacrylate and vinyl chloride acrylonitrile are 100 ~ 130 ℃, 85 ℃ and 140 ~ 150 ℃ respectively.

2 PVC chlorination

It is prepared by chlorination of PVC resin, and its chlorine content is 62% ~ 68%.Chlorinated polyvinyl chloride can be used continuously at 100 ℃ (20 ~ 35 ℃ higher than PVC), and the maximum service temperature can reach 100 ~ 105 ℃, and its chemical stability, flame retardancy and cold resistance are better than PVC. However, the strict anti-corrosion requirements of chlorination equipment, difficult processing of resin and poor impact toughness restrict its application and development.

3 PVC Crosslinking

Crosslinked PVC can be prepared by radiation crosslinking method and chemical crosslinking method. The crosslinked PVC products have higher mechanical strength, good dimensional stability, heat deformation resistance, wear resistance and chemical resistance than ordinary PVC products. The radiation crosslinked wires can be used continuously at 100 ~ 110 ℃.

4 PVC Blending with other polymers

When PVC is mixed with other polymers in a certain proportion, the properties of the blends (fully compatible) are improved compared with PVC. Because the two polymers with compatibility can reach molecular level mutual fusion and form single-phase structure after mixing, so as to supplement and strengthen the properties of the blends, such as PVC / PS, PVC / PE, PVC / CPVC and so on.

5 Add heat-resistant modifier

Heat resistant modifier is a kind of polymer with high heat resistance developed and produced to improve the heat resistance of PVC.

(1) Polyglutarimide: prepared by the reaction of polymethylmethacrylate and CH3NH4;

(2) SMA (styrene maleic anhydride copolymer) is a good heat-resistant modifier for PVC introduced by American manufacturers;

(3) Ht-510 (Japan) is a series of propylene imine based copolymers. It is a heat-resistant additive that can effectively improve the practical high temperature resistance of PVC mixture for transparency and opacity.

6 PVC Adding inorganic value material to

Adding a certain amount of filler can improve the heat resistance of PVC. Common fillers include: heavy calcium carbonate, light calcium carbonate, precipitated calcium carbonate, calcined pottery, barium sulfate, red mud, titanium self powder, etc.

7 PVC Adding glass fiber to

Adding 20% ~ 30% glass fiber into PVC can improve its heat resistance to more than 100 ℃.It makes PVC resin and glass fiber bond well without (or less) plasticizer, especially for long fiber reinforced PVC, the increase of thermal deformation temperature is more obvious.

 8 Ordinary CPVC improves Vicat

The processing performance of materials will become worse, which needs to be offset by adding impact modifier. Using α-If methyl styrene to increase Vicat (every 1% of Vicat is increased by 2-3 ℃), the processing temperature will be increased and the physical and mechanical properties will be reduced, but the range is smaller than that of CPVC. At the same time, impact modifier should be added to offset it.

9Some varieties of PVC heat-resistant modifiers:

   Japan Zhongyuan TELALLOY A15 is a heat-resistant modifier for PVC of ABS system, which can greatly improve its heat resistance without damaging the inherent characteristics of PVC resin. The use of this product in soft and semi-hard artificial leather can greatly improve its wrinkle retention.

    Japan Zhongyuan TELALLOY A50B is a heat-resistant modifier for PVC of ABS system.

GE- BLENDEX 587 (b587) resin modifier (heat variant temperature improver) is a special polymer used to improve PVC homopolymer and copolymer products, providing excellent high temperature resistance, Vicat B120 / 49n 127 degrees

GE-BLENDEX 586 (B586) resin modifier (increasing heat deformation temperature agent) is a special polymer used for improving PVC homopolymer and copolymer products, providing excellent high temperature resistance, Vicat 120 degrees. 

GE-BLENDEX 703 (B703) (70703)) resin modifier (B586 70% + 338 30%) is specially used to improve the thermal deformation temperature and toughening effect. It can be made into alloy with bas and PVC to improve the heat resistance and impact modification of products.