It's cold, will the foam shrink?

When the weather is cold, the foam will shrink. However, the disadvantages are also caused by this kind of soft elastic, that is, short service life, easy surface cutting, large compression deformation and average running stability.

Polypropylene foam is a kind of high crystalline polymer/gas composite with excellent properties. With its unique and superior performance, it has become the fastest developing new type of environmental protection, pressure resistance, cushioning and heat insulation material.

EPP products have excellent seismic energy absorption performance, high recovery rate after deformation, good heat resistance, chemical resistance, oil resistance and heat insulation. In addition, their weight is very light, which can greatly reduce the weight of articles. EPP is also an environmentally friendly material, which can not only be recycled, but also be naturally degraded without causing white pollution.

The application of EPP is more and more extensive. IT products, electronic communication equipment, liquid crystal display, plasma color TV, precision electronic components, precision instruments, etc. Everyone began to use EPP as packaging material.

Another particularly important application field is a large number of applications in the automobile industry: automobile bumper, automobile side shock-proof core, automobile door shock-proof core, advanced safety automobile seat, toolbox, trunk, armrest, bottom pad, sun visor and so on. (According to statistics, at present, every car uses plastic 100~ 130kg on average, of which EPP plastic is about 4~6kg).

Foam is a material formed by foaming plastic particles, referred to as foam. Foams are divided into PU foam, antistatic foam, conductive foam, EPE, antistatic EPE, and? CR, EVA, bridging PE, SBR, EPDM, etc. Foam has a series of characteristics such as high elasticity, light weight, rapid pressure-sensitive fixation, convenient use, free bending, ultra-thin volume and reliable performance.

The molecular weight distribution of EPDM can be determined by gel permeation chromatography at high temperature (150℃) with dichlorobenzene as solvent. The molecular weight distribution is usually called the ratio of weight average molecular weight to number average molecular weight.

This value ranges from 2 to 5, depending on the common and highly branched structures. Due to the separation of bonds, the molecular weight distribution of EPDM containing DCPD is wide.

By increasing the molecular weight of EPDM, the positive effects are: higher tensile and tear strength, higher green strength at high temperature, and more oil and filler absorption (low cost). With the increase of molecular weight distribution, the positive effects are: increasing the mixing and milling performance. However, narrower molecular weight distribution can improve curing speed, curing state and injection molding behavior.

The above content source: Baidu Encyclopedia-Bubble