韩国国产精品999久久久,亚洲欧美久久精品免费,日韩精品无码熟人妻视频,精品亚洲一区二区不卡

English abbreviation of material: EVAChinese name of material: ethylene-vinyl acetate copolymerFull English name of material: ethylene-vinylacetatecopolymerEVA basic parameters:Relative density 0. 92～0。 ninety-eightRefractive index 1. 480～1。 five hundred and tenBrittleness temperature<- 60 ℃Thermal decomposition temper……

Bubble bag is a kind of green and environment-friendly new shockproof cushioning material. Bubble bag is also known as air cushion film, bead rubber, bubble roll, etc. Processed with low density polyethylene, it is a transparent flexible packaging material widely used at present. The principle is that the film contains……

Pearl cotton packaging materials have many advantages, such as water and moisture resistance, shock resistance, sound insulation, heat preservation, good plasticity, strong toughness, recycling, environmental protection, strong impact resistance, etc., and also have good chemical resistance. It is an ideal substitute f……