Polymer polyurethan

Polymers. Polyurethane foam has been prepared from the lactose in dried whey by reaction with dimethyl sulfoxide (Hustad et al. 1970). 

D. Jhurry and A. Deffieux, Sucrose-based polymers Polyurethanes with sucrose in the main chain, Eur. Polym.. 1, 33 (1997) 1577-1582. 

Sodium ion-selective field-effect transistors (Na+ ISFETs) were prepared by using three different types of polymeric matrix materials, such as polyvinyl chloride, bio-compatible polymer (polyurethane) and Urushi (natural oriental lacquer). Their electrochemical characteristics were discussed in connection with their characteristics of polymeric matrix membranes. 

The carbon dioxide that is produced by the preceding equation is trapped in the polymer as it forms, resulting in a foamy polymer. Polyurethane foam is used to make cushions, pillows, and insulation. 

Other Photofragmentations - [4+4] Cycloadducts of anthracenes and furan are both formed and cleaved photochemically. (o-Anthrylpolystyrenes have been shown to undergo reversible photodimerization, allowing photochemical control of molar rnass. The cycles can be conducted more than ten times without detectable degradation of the polymers. Polyurethanes and poly-ethers containing coumarin components exhibit similar reversible photopolymerization and cleavage. 

Often a textile fabric requires a firm feel or hand. This can be accomplished by adding a chemical finish to increase the fabric stiffness. These finishes are usually low-cost water-soluble polymers such as starch or polyvinyl alcohol. If a durable stiffening effect is needed, vinyl acetate polymers, polyurethanes and thermosetting resins can be used. 

Sorbitol is an interesting natural monomer obtained from glucose (sugar waste is used for this purpose) by dehydrogenation. It easily dehydrogenates into isosor-bide which is useful as a polyol for production of polymers/polyurethane [69, 70]. 

The term "condensation polymers" was introduced by W. H. Carothers in his early work on the preparation of polyesters and polyamides to distinguish this class of polymers from vinyl polymers made by addition reactions. Condensation polymers were defined as polymeric molecules that may be converted by hydrolysis, or its equivalent, into monomers that differ from the structural units by one molecule of H2O, HCl, NHj, etc. This broad definition includes many polymers made by ring-opening or addition reactions, for example, lactone and lactam polymers, polyurethanes, polyureas, polyimides, and polyhydrazides, as well as polymers made by true condensation reactions. 

Unique Properties of Foamed Plastics Structural Features of Foamed Plastics Leading Commercial Polymers Polyurethane Polystyrene Poly(vinyl chloride)... 

Free-Flo. [Cook C( nposites Polymers] Polyurethane foam. 

Rucothane. [Ruco Polymer] Polyurethane latex used as fiothable interiayer/ adhesive, as saturant and binder for nonwovois, and as blending resin f< odier latexes. 

The valuable polymer polyurethane is made by a condensation reaction of alcohols (ROH) with compounds that contain an isocyanate group (RNCO). Two reactions that can generate a urethane monomer are shown here ... 

Tar-based products are used in conjunction with polymers in the manufacture of polymer-reinforced membranes which are biostable and moisture impermeable. In this combination, polymer (polyurethane or some styrene-containing block copolymers) offers reinforcing network but it is also plasticized to produce elastomeric materials having excellent... 

Among the many types of processible NLO polymers, polyurethane with symmetrical substituted tris-azo dye with fluorinated alkyl units (PSTF for short) was selected as a waveguide material. PSTF is a novel third-order NLO main-chain polyurethane with tris-azo dye incorporated into the main chain with a fluorinated alkyl backbone [40]. This polymer is similar to the SBAC polymer family whereby a symmetrically substituted 7t-conjugated molecule was incorporated in a main-chain polymer. Azo dye is an effective NLO dye investigated by many researchers and the tris-azo dye is very special for NLO applications. Fluorinated alkyl units are expected to be effective for reducing the polymer... 

Thermosets are rigid polymers that do not melt upon heating. They are densely cross-linked polymers. Polyurethanes, epoxy resins and phenol-formaldehyde resins are some important thermoset polymers. 

Y. Wei, C. Zong, F. Wang, Preparation of vinyl polymer/polyurethane hybrid latex particles and their application in nano-sized vinyl polymer particle/thermoplastic polyurethane blends, E-Polymers 10 (1) (2010). 

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