Explanation

It is also called polyurethane, or polyurethime for short. It is formed by the reaction of isocyanate and polyol. Linear thermoplastic resin or thermosetting resin can be prepared according to the number of functional groups contained in the polyol. According to the different polyols of raw materials, there are polyester type and polyether plastic; According to the degree of crosslinking, there are two types: thermoplastic and thermosetting; According to the processing method, there are three types: casting type, thermoplastic type and mixing type. Due to different raw materials, the polymer formed have different structures and different properties. Polyurethime soft foam and hard foam play an important role in polyurethime plastics, accounting for more than 80% of the total consumption of polyurethime. Soft products account for about 60%, while hard and semi hard products account for 40%. Soft polyurethane foam is characterized by soft texture, low density, high elasticity, sound absorption, heat insulation, oil resistance and cold resistance, and is widely used in industry and daily use. Hard polyurethane foam has low density, heat insulation and sound absorption. It is widely used as noise elimination, heat insulation, shock absorption and packaging materials in industry, construction, ships, vehicles, machines, instruments, etc. In addition to being used as foamed plastics, polyurethime is also used as elastomer, fiber, coatings, synthetic leather, adhesive, waterproof materials, building materials, biomedical materials, etc.

Classification