What are chemical properties of Expanded Polystyrene

Polystyrene known as polystyrene and styrene copolymer, is a mixture of resin and a physical blowing agent and other additives. Can be made of PS can be processed into a product density foam agent. The most common polystyrene containing pentane as a blowing agent transparent PS pellets. The system can be made of polystyrene foam products out there are a few special steps, which is a characteristic of many plastic resins (including polyolefin molded foam and copolymer). Can be made of PS can be used to manufacture a variety of products such as coffee mugs, absorb the energy of an automobile shock absorber or 300 ft3 large foam blocks. The main purpose of EPS disposable beverage cups, packaging and seismic insulation.

Polystyrene resin is granular, diameter is generally 0.01-0.1in. Most of these particles are beads produced by suspension polymerization, and particles larger diameter may also be obtained by pelletizing. The size of the beads is determined using a minimum wall thickness of the final foam product. Larger particles made of low-density expanded foam products easier, smaller particles are more easily made uniform filling of parts.

Properties of the foam product depends on the base polymer, but influenced by the great density of the foam. A density of 11b / ft3 foam product of S 97% of the volume is air, the poor mechanical properties of this product. The air contained in the foam divided into millions of cells, it is their presence that the polymer foam has many valuable features. These features include thermal insulation, energy absorption, floating, high stiffness / weight ratio and lower cost per unit volume and so on. As shown in Table back, most of the performance of all its density foam PS there was a clear function, so producers can die without re-design of the actual operation only minor adjustments needed to do simple processing changes. Other properties of PS foam also depends on the type and amount of polymer foam when used. Since the mechanical strength of the foamed product of PS foam density can be adjusted, so sometimes by choosing another polymer foam to get the required strength. One example is to obtain the strength not belong performance, so as to improve its own PS does not have heat resistance and solvent resistance; Another example is the use of a polyolefin or olefin / styrene copolymer, can improve the flexibility or elongation rate, but the strength is improved much.