Polyurethanmaterials [that is, high molecular polymers containing urethane groups and -NHCOO in the main chain of macromolecules] have developed rapidly since the industrial production was not released on the market in the 1950s. Compared with polymer rubber materials, it has its own unique characteristics. It can use different numbers of functional groups and different types of functional groups according to different performance requirements, and use different production processes to produce polyurethan products with different properties and properties.
Among rubber rubber types, there are polyurethan rubber varieties that can be cross-linked. There are also those that are not in the category of rubber, such as foam plastics, rigid plastic products, coatings, high resilience synthetic fibers, artificial leather, adhesives, and so on.
Polyurethan materialer er i øjeblikket meget udbredt på forskellige områder. For eksempel i luftfartsindustrien er dets hårde produkter, bløde produkter og skumprodukter lettere end metalmaterialer, [meget vigtigt for fly], og har høj modstandsdygtighed og ikke-antændelighed. , Højstyrke, ultra-lav temperaturisolering osv., Der bruges til flyhætter, hastighedsbremser, radomer, flybrændstoftankfyldere, brændstofforbrugsstyrede fordamperbøjer osv., Samt forskellige understøtningsrammer og sædehynder til indvendig dekoration . Det bruges til varmebesparelse i transportindustrien.Polyurethanmaterialer er uadskillelige fra materialer og sædehynder, fremstilling af hjemmemøbler og endda avancerede voksne kondomer og dæk. Og den nylige udvikling og brug af produkter inden for bilstøddæmpning og dæmpningstilbehør har tiltrukket sig mere opmærksomhed.
Although there are many types of polyurethan products, the classification of its products is nothing more than:
Flexible foam products, rigid products, and elastomers [thermoplastic elastomers, vulcanizable elastomers EU, AU]. The product molding equipment, such as mixing polyurethan rubber, is generally solid and can be vulcanized with sulfur, peroxide, and polyisocyanate. It can be designed according to the conventional rubber product production process and formula. If it is a thermoplastic elastomer, it can be injection or compression molding. If it is a plastic polyurethan, det kan fremstilles ved en støbemetode. tager fleksibelpolyurethan foam products as an example, the composition of the formula, the main reactants of which are polyether, polyester, or other polyols; and polyisocyanates. Others include water [chain extender], crosslinking agent, catalyst, foam stabilizer, external blowing agent, flame retardant, mold release agent, coloring agent, etc. The production process is generally two-component liquid reaction molding. That is to say, one group is that the polyol polymer and the isocyanate are mixed and reacted first, and then the above reactants are mixed with another group including water, blowing agent, stabilizer, catalyst, and various auxiliary agents to produce organic carbamate. At the same time, the reactants such as urea group use the reaction to generate carbon dioxide, release a large amount of heat, vaporize the added blowing agent, and then use the catalyst to adjust the foaming speed, and finally complete the product with uniform foam structure. At present, the automobile manufacturing industry has continuously improved safety, comfort, and durability, and has high requirements for durability in high-strength working conditions of shock-absorbing and damping elastomer parts. A new type of shock absorber made of polyurethan flexible foam has appeared in foreign markets. Its physical and mechanical properties and damping effect are slightly better than rubber damping accessories. The product requires a density of 0.08g 丿cm3, a material compression of 5%, a compressive strength of more than 7Kpa, the product works normally at -20-40 "degrees", the product's compression set is not more than 10%, and it has oil resistance. Under pressure impact, no fracture occurs. The production process is not special. The key lies in its main reaction material. Currently, BASF is monopolizing the production and supply. BASF also learns from DuPont's market supply principle of perfluoroether rubber, which is to sell only finished products, not raw materials. , In order to achieve the reduction of market competitors.
Denne nye typepolyurethanfleksibel skumbil stødabsorberende dele vedtager en avanceret "et-trins" støbeproces, det vil sige alle komponenter i råvarerne i formuleringen, såsom isocyanat, polyolpolymer, kædeforlænger, katalysator, skumstabilisator og andre Hjælpemidlet måles i henhold til formlen med isocyanat som en separat komponent, og forskellige hjælpemidler, såsom polyolpolymer, vand, hjælpeblæsemiddel, kædeforlænger, overfladeaktivt stof, katalysator osv. forberedes til en komponent, og derefter tilsættes en gang det til reaktionstanken, og tilsæt derefter skummidlet. Efter omrøring og blanding med høj hastighed udføres den skummende reaktionsproces. Denne et-trins produktionsproces er særligt velegnet til behandling af tilbehør med komplekse former og små specifikationer. Ved støbemetoden injiceres den blandede væske direkte i en form med en kompliceret form og skummes derefter i formhulrummet til formning. Produkter fremstillet ved denne metode. Specifikationerne og målene er nøjagtige, og det kan også bruges som metalindlagte produkter efter behov.
Polyurethanproducts are currently widely used and the market demand is also large. Although my country started late, it has developed rapidly. Its global market share has reached more than a quarter. It has become the world's largest manufacturing and consumer market for polyurethan products. However, there is still a gap between the key main reaction materials and the advanced foreign level, and the industry needs to work hard to innovate and develop.It is reported that retreading tires with polyurethan material as tread rubber has better wear resistance and environmental protection than natural rubber. This innovative research and development has opened up a new way for retreading. During the "13th Five-Year Plan" period, the polyurethan industry will have more room for development.
