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At or near the final stages of production, the material is treated with a chain extender. Typically, chain extenders are bifunctional, i.e., they have two functional groups, which can link together two polymers. Representative classes of chain extenders are diglycidyl ethers, diols, diamines, or dianhydrides. Chain extenders are often applied ...
2-Methylpentamethylenediamine can also be used as a chain extender for polyurethane applications, and in particular with PUDs. [3] [4] Its derivatives like aspartic esters, secondary amines, aldimines and ketoimines serve as curatives in polyurea systems. In polyamides, 2-Methylpentamethylenediamine acts as a crystallinity disruptor.
TPU is a block copolymer consisting of alternating sequences of hard and soft segments or domains formed by the reaction of (1) diisocyanates with short-chain diols (so-called chain extenders) and (2) diisocyanates with long-chain diols. By varying the ratio, structure and/or molecular weight of the reaction compounds, an enormous variety of ...
Chain extenders (f = 2) and cross linkers (f ≥ 3) are low molecular weight amine terminated compounds that play an important role in polyurea compounds, elastomers and adhesives. DETDA is one such amine and is used extensively in reaction injection molding (RIM) and in polyurethane and polyurea elastomer formulations.
1,6-Hexanediol can improve the hardness and flexibility of polyesters as it contains a fairly long hydrocarbon chain. In polyurethanes, it is used as a chain extender , and the resulting modified polyurethane has high resistance to hydrolysis as well as mechanical strength, but with a low glass transition temperature.
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This polymer has high molar masses without the use of a chain extender. Since then, several PBS producers such as Hexing Chemical (Anhui, China), Xinfu Pharmaceutical (Hangzhou, China) or IRe Chemical (South Korea) appeared on the market. In 2010 Hexing Chemical became China's first large-scale PBS enterprise, with the annual capacity of 10,000 ...
One of the biggest decisions anyone has to make for retirement is where to invest money. If you ask 10 different financial advisors, there is a 100% chance you’ll get 10 different answers. This ...