According to the different uses, PVC plastic is divided into: no plasticized PVC, plasticizer content is 0, rigid PVC, plasticizer content is less than 10%; semi-rigid PVC, plasticizer content of 10-30%; soft PVC, plasticizer content of 30-70%, PVC paste plastic, plasticizer content is more than 80%.
Plasticizer content in export PVC products: as early as December 7, 1999, the European Union issued a provisional injunction 1999/815/EC (2004/178/EC ninth Extension of the temporary ban), prohibiting the use of six phthalates in soft poly-vinyl chloride toys for children under three years old, i.e., DINP, DEHP, DNDP, BBP, DBP, cannot exceed 0.1% of the total weight.
The main role of plasticizer and PVC mixture is to reduce the melt temperature and melt viscosity of the polymers, thus reducing the temperature of forming and processing, so that the polymer products have flexibility, elasticity and low-temperature resistance. The main purpose is to improve the physical properties required. The types and concentrations of plasticizers (i.e., content) are the two main factors that affect these properties.
The dosage of PVC plasticizer has different effect. Firstly, the effect of the mechanical strength of PVC plasticizer under 10 parts is not obvious. But when the PVC plasticizer plus about 5 parts, the mechanical strength is weakened, this is the phenomenon of anti-plasticizing. So the general rigid products do not need to add PVC plasticizer or a little more in it. In some cases in order to improve the processing liquidity will choose to add a little PVC plasticizer. However, if it is a soft product, you need to add more quantity to make the product softer. The total quantity of plasticizer for PVC should be added according to the requirements of the softness of the products and the use, process and environment. In the process of calendering production of PVC film, plasticizer total dosage is about 50 parts. PVC Plasticizer selection method: a. According to the product of soft and rigid degree selection, the general plasticizer of rigid products is added to 0~5, the plasticizer of semi-rigid products is 6~25, the plasticizer of soft products is 30~70, the plasticizer of the paste product is 60~100. B. The main and assistant plasticizers are selected together. c. According to the performance requirements of PVC products, such as whether the requirements of non-toxic, cold, insulation, antibacterial, biological degradation, etc. to select. d. Consider reducing the cost factors of PVC products, can choose epoxy fatty acid ester, epoxy soybean oil, DOTP, glycerol ester and other cheap plasticizer.