(1) to improve the principle of transparency of the plastic to reduce the degree of crystallinity, control the quality of clean, improve the refractive index, reduce the birefringence.
(2) methods to improve the transparency of plastics
① Add nucleating agent: This is the most effective way to improve the transparency of transparent resin, it can promote the crystallization of small molecules in the resin can play the role of nuclei, so that the original homogeneous nucleation into different Phase nucleation, increase the number of crystal nuclei in the crystal system, the number of microcrystals increased, the number of spherulites decreased, so that the crystal size is thinner, the transparency of the resin increased. Many types of nucleating agents can be divided into two kinds of transparent nucleating agents (sorbitol, phosphorus) and standard nucleating agents (carboxylic acids, carboxylates, inorganic substances). As a transparent modified nucleating agent, generally choose a transparent nucleating agent; sometimes can use standard nucleating agent, but to strictly control the amount of added.
② blending to improve the transparency of plastic, that is, in the transparent resin by adding small molecules, improve transparency.
③ two-way stretch to improve the transparency of plastic, products can be broken in the original crystal particles to make the crystal size smaller, to achieve the purpose of improving the light transmittance.