The molecular structure of PET plastic is highly symmetric, and it has certain crystallinity orientation ability, so it has high film-forming property and forming property.PET plastic has good optical properties and weather resistance, and amorphous PET plastic has good optical transparency.In addition, PET plastic has excellent abrasion resistance, dimension stability and electrical insulation.PET bottles are widely used because of their high strength, good transparency, non-toxic, anti-permeability, light quality and high production efficiency.The structure of PBT and PET molecular chain is similar, and most of the properties are the same. However, the main chain of the molecule is changed from two methylene to four methylene, so the molecule is more smooth and the processing performance is better.

PET is a high crystallinity polymer of milky white or light yellow with smooth and glossy surface.Creep resistance, fatigue resistance, good friction resistance, low wear consumption and high hardness, with the largest toughness of thermoplastic;The electrical insulation performance is good, less affected by temperature, but less resistant to corona.Non - toxic, weather - resistant, anti - chemical stability of good, high moisture absorption, pre-molding drying is necessary.Resistant to weak acid and organic solvent, but not heat - resistant water immersion, non - alkali.

PET resin has high vitrification temperature, slow crystallization speed, long molding cycle, long molding cycle, large shrinkage rate, poor dimensional stability, brittleness and low heat resistance.