What is the difference between polyurethane and plastic?
The acetone extractives are some fatty acids and steroids, some natural antioxidants and accelerators, and can help with the powdery agent in the process of mixing and dispersion of rubber softening effect. Ash containing mainly magnesium phosphate and calcium phosphate salts, copper, manganese, iron and other metal compounds is very small, because these valence metal ion can promote the aging of rubber, so their content should be controlled. Dry glue in water does not exceed 1%, in the process can be volatile, but the moisture content is too long, will not only make the rubber easy to mildew during storage, but also the impact of rubber processing, such as mixing with the agent is easy to agglomerate; easy to blister calendering and extrusion process, the bubble or a sponge in the process of sulfur etc..
Polymerization methods vary with material properties. Synthetic elastomer before preparation of low molecular weight diols, with excessive aromatic or aliphatic isocyanate reaction, generating isocyanate (-NCO) terminated prepolymer and polyol, chain extender, thermoplastic elastomer obtained by two yuan; if the diamine chain extender and further crosslinked to casting elastic body. The prepolymer obtained elastic fiber by hydrazine or two amine chain expansion; the prepolymer with too much isocyanate was mixed with catalyst and foaming agent to obtain the rigid foam. If the monomer, polyether, water, catalyst and other mixed, a step reaction can be obtained soft foam. The monomer reacts with polyols in solution to obtain paint; the adhesive mixes and reacts with polyisocyanate monomers and low molecular weight polyesters or polyethers in use. The polyurethane elastomer used for roller, conveyor belts, hoses, auto parts, shoe soles, synthetic leather, artificial organs and medical cable; soft foam cushion for a vehicle, bedroom, clothing, rigid foam for insulation, sound-absorbing, packaging, insulation and low foaming synthetic wood, paint, furniture for advanced vehicles wood and metal door, pond dam and building waterproofing materials and fabric coating etc.. Adhesives have good adhesion to metals, glass, ceramics, leather, fibers, etc.. In addition, polyurethane can be made into emulsion, magnetic material and so on
Polyurethane polyurethane material is the best thermal insulation material in the world at present. A class of polymers containing NHCOO - repeating structural units in the backbone. English abbreviation PU. Formed from the polymerization of an isocyanate (monomer) with a hydroxyl compound. Because of the strong polarity of urethane group, insoluble in non-polar group, it has good oil resistance, toughness, wear resistance, aging resistance and adhesion. Materials suitable for a wide range of temperatures (50 to 50 DEG C) can be prepared from different raw materials, including elastomers, thermoplastic resins, and thermosetting resins. High temperature resistant to hydrolysis, but also resistant to alkaline medium. Commonly used monomers, such as toluene diisocyanate, two benzene diisocyanate, etc.. Polyols are classified into three groups: simple Polyols (ethylene glycol, glycerin, etc.);
Rubber is made from latex, and a portion of the non - rubber contained in the latex is left in the solid rubber. In general, natural rubber contains 9, two,%-95% of rubber, not 5%-% of rubber hydrocarbons. Because of the different processing methods, different habitats and even different seasons, the proportion of these ingredients may vary, but basically within the scope. Proteins can promote the vulcanization of rubber and retard aging. On the other hand, the protein has strong water absorption, can cause rubber moisture absorption, mildew, insulation degradation, protein and increase heat generation shortcomings.
Rubber and polyurethane are two different materials. The advantages of its use are slightly different, so to speak, rubber is the most widely used. Rubber is a latex made from rubber, tree, rubber, and grass. It is made of flexible, insulating, impermeable and air. High elastic polymer compound. It is divided into two kinds: natural rubber and synthetic rubber. Natural rubber is made from rubber, tree, rubber, grass and other plants. The synthetic rubber is obtained by polymerization of various monomers. Rubber products are widely used in industry or in all fields of life.
