The structure of synthetic resin with similar structure is limited, and the structure of plastic additives is complicated. Not every polymer selection of plastic additives should choose varieties with similar structure, but plastic additives with similar structure and basic resin can really improve the efficacy of plastic additives and the comprehensive performance of products. For example, an antioxidant with an amide structure is 1098 used for nylon, and the stabilizing effect is much better than that of the antioxidant 1010, and the extraction resistance is also significantly better than the latter, while the antioxidant is 1098 used for polyolefin or polyester, without any advantage.
The difference in polar polarity directly affects the compatibility of plastic additives with the base resin. The polarity of plastic additives does not match the matrix resin, resulting in poor compatibility, which is manifested as a decline in the physical and mechanical properties of the product, precipitation of plastic additives, surface blooming, shortening the durability of the efficacy of plastic additives, discoloration of the product, and reprocessing of the product. Therefore, non-polar or weak polar polymers should choose non-polar auxiliaries, while polar polymers should choose polar auxiliaries. For example, cationic antistatic agents for PVC, the effect is significant; and for PE or PP, it can not achieve the desired effect. For another example, the addition amount of dripping agent for agricultural PVC greenhouse film can reach 3% ~ 4%; For the production of EVA greenhouse film, the addition amount of dripping agent is 1.5~2.5; However, for the production of PE greenhouse film, the dripping agent can only be added by 1.2~1.8, otherwise a layer of white precipitate will soon be produced on the surface of the greenhouse film.