Plastic packaging material thermal stability of PVC plastic profile

Tech pack material thermal stability of PVC plastic profile heat stabilizer is heat stabilizer in PVC resin, additives to improve PVC thermal stability at high temperature. Generally considered heat stabilizer are a common feature, that is the acceptor hydrogen chloride, can have the effect of capture hydrogen chloride produced by decomposition of PVC, and prevent because of the existence of system of free hydrogen chloride and promoting effect on thermal decomposition of polyvinyl chloride (PVC). Some heat stabilizer such as cadmium salt, also with allyl chloride ligand in polyvinyl chloride (PVC) or reaction and stabilizing with it. The main compounds can be used as PVC stabilizers are metal mound ( Such as zinc stearate, calcium stearate, stearic acid, such as lead, cadmium stearate barium stearate) And organic tin compounds ( Such as lauric acid tin, tin maleic acid, etc. ) , epoxy compound ( Such as epoxy soybean oil) And so on. Heat stabilizer heat resistance is the main performance index, frosting, and sweating, sulfide pollution resistance, etc. 1) Heat resistance. Heat resistance can be divided into static heat resistance ( By test tube method, thermal drying method or hot pressing method of heat resisting performance, reflect the pure chemical reaction under the static heat resistance) And the dynamic heat resistance ( By a double roller machine or plasticizing instrument measured heat resistant properties, is associated with the role of mechanical force) , which can reflect the effect of thermal stability during processing. Some organic tin stabilizer such as maleic acid lipid, static thermal stability is good, but the lubrication is not good enough, so dynamic poor heat resistance, applications often need with the proper lubricant. Also need attention early is heat resistance and thermal stability problem for a long time. Barium soap, for example, the stability of the system of polyvinyl chloride (PVC), in the process of thermal aging, early will become pink, and the thermal aging for a long time after the color changes are less; Cadmium soap and stable system of polyvinyl chloride (PVC), at the beginning of the thermal aging process thermal stability is good, but after heat aging for a long time will become black. The synergies and a heat stabilizer, the reasonable matching of composite stabilizer, its stable effect is significantly higher than that in composite stabilizer single stabilizer effect of thermal stability. 2) Frosting and sweating. When the stabilizer and the compatibility between polyvinyl chloride (PVC) resin, with people into the polyvinyl chloride (PVC) plastic, will move from inside the products to the surface of the products. Jorge stabilizer for solid, and move to the surface of the product is called & other; Frosting & throughout; ; Jorge stabilizer for liquid, and move to the surface of the product is called & other; Sweat & throughout; 。 Frosting and sweat can in the following ways to avoid: control easy frosting and sweat of the quantity of heat stabilizer, or by some small amount of frosting inhibitors, such as barium laurate, liquid barium/cadmium stabilizers, etc. 3) The sulfide pollution resistant. Some stabilizers in sulfur, hydrogen sulfide and other sulfide, generates the ferrous sulfide and make the products color and pollution, stabilizing agent of sulfur and sulfide discoloration of ability call sulfide pollution resistant.