The difference between polyurethane foam and polyurethane rubber
We know that both polyurethane foam and polyurethane rubber are made of polyurethane materials, but there are big differences between the two, both in terms of application range and performance characteristics, this article introduces polyurethane foam and polyurethane rubber in detail difference between.
Polyurethane material is a very high polymer. It is composed of a hard segment and a soft segment. The Tg of the hard segment is very low and has the characteristics of plastic. The Tg of the soft segment is much higher than the indoor temperature and has the characteristics of vulcanized rubber. In the whole process of the production of the polyurethane material, according to the manipulation of the polymerization reaction, the proportion of the hard segment and the soft segment of the polymer can be adjusted, so that the polyurethane material is mainly represented by plastic or vulcanized rubber. Next, let's talk about the difference between polyurethane sponge and polyurethane rubber.Polyurethane sponge refers to a low-density sponge with a sponge density of less than 18 kg per cubic meter. Generally, the amount of water exceeds 4.5 parts, that is, the amount of TDI exceeds 55 parts per 100 parts of polyol. The heat dissipation problem of the foam sponge is very prominent. The heat inside the foam is not easy to dissipate. During the foaming process, the temperature automatically rises to more than 180 degrees Celsius, which can cause the spontaneous combustion of the foam sponge, and there is a danger of fire.Polyurethane rubber is mainly composed of polyester or the polymerization of polyether and diisocyanate compounds. Unlike foam, its chemical structure is much more complicated to compare with ordinary elastic polymers, except for the recurring urethane In addition to ester groups, there are often ester groups, ether groups, and aromatic groups in the molecular chain. This rubber has very high hardness and strength, as well as the high elasticity and high wear resistance of sponge. The characteristics of resistance, tear resistance and aging resistance, and its ozone resistance, radiation resistance and conductivity are also very good.
