Release time: 2020-01-19 05:22:59
The one-component polyurethane waterproof coating does not contain coal tar, petroleum resin, asphalt and organic solvents. It has no pollution to the human body and the environment, and can be made into various colors to beautify the environment. The one-component polyurethane waterproof coating is easy to construct, which overcomes the disadvantages of the two-component polyurethane waterproof coating that requires metering and stirring, and ensures the product quality and engineering waterproof effect.
1000D and 2000D are used in the production and synthesis of polyurethane leather finishing agents. Their polymers have good strength, abrasion resistance and solvent resistance.
Effects of modification on the heat resistance of polyurethane elastomers 1) Silicone modification: Silicone-modified polyurethane elastomers have high heat resistance, and their heat distortion temperature can reach 190 ° C. . 2) Introduction of intramolecular groups: The thermal decomposition temperature of polyurethane elastomers mainly depends on the heat resistance of various groups in the macromolecular structure. If there are double bonds in the soft segment, the heat resistance of the elastomer will be reduced, and the introduction of isocyanurate ring and inorganic elements can improve the heat resistance of the polyurethane elastomer. 3) Compounding with nanoparticles and fillers: Nanomaterials are "the most promising materials in the 21st century", and polymer-based nanocomposites mean that the size of their dispersed phase is at least one dimension in the nanometer range. Due to the unique properties of the nanoparticles, the mechanical properties are significantly improved by compounding them with polyurethane elastomers, and they can increase the heat resistance and aging resistance of the elastomers. The silicate in the soil acts as a heat insulator and can effectively improve the heat resistance of the composite. The mechanical properties and heat resistance of micron-sized inorganic filler-modified polyurethane elastomers are significantly better than ordinary polyurethane elastomers.
In China, trimethylolpropane is mainly used as a raw material for the synthesis of high-grade alkyd resin paints, and its consumption accounts for about 85% of the total domestic TMP consumption.
The outer insulation system of polyurethane insulation board has good fire resistance. Because rigid polyurethane foam is a thermosetting material, carbon deposits will be formed after burning in a fire. As the carbon deposits thicken, they isolate heat and oxygen transfer and form a flame retardant or non-combustible layer to prevent further flame diffusion.
Polyether (basic polyether) for soft furniture foam sponge, used for soft polyurethane block foam material, packaging, seat cushion material, suitable for medium and high density foam
Casting polyurethane elastomer (referred to as CPU)-it is the most widely used and most productive type of polyurethane elastomer;
TDI and MDI are both the main raw materials of polyurethane, but due to the difference in structure and performance, the subdivision uses are very different.
Most water-based polyurethanes do not contain the -NCO gene, so they are mainly cured by the cohesive force and adhesion of polar genes in the molecule.
Different types of micro-irrigation equipment and various geotechnical materials for canal anti-seepage pipes and anti-seepage membranes can meet the needs of water-saving agricultural development. The building structure is unstable, and the insulation layer is prone to cracks. The structure is made on the outside of the main structure, which is equivalent to adding protective clothing, medicines and other plastic packaging to the entire building to improve protection and extend the life of the goods. The surface changes greatly, and its structural composition is sprayed polyurethane rigid foam insulation layer, polyurethane interface layer, screed layer, glass fiber mesh anti-crack mortar protective layer, and decorative layer.
MDI uses aniline as a raw material, reacts with formaldehyde, condenses in an acidic solution, neutralizes with a base, and then distills to obtain diaminodiphenylmethane, which can be prepared by reacting with phosgene and then refining.