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Condensation polymers modified through

Thermogravimetric Data For Polymers Modified Through Condensation With Group IV A and B Reactants... [Pg.66]

Ferrocene containing condensation polymers have been utilized by us to modify the surfaces of electrodes.Materials of this type that incorporate organo-iron compounds into a polymer matrix, either through chemical bonding or by formation of blends, have the potential of being thermally processed to yield iron oxides. [Pg.460]

Most polymers that function properly at ambient temperature quite frequently have limited performance at sustained elevated temperatures. This invariably limits the utility of polymeric materials. The low thermal stability is generally due to decreased crystallinity and/or thermal decomposition. Polymer chemists have, through some ingenious ways, synthesized polymer — such as aromatic polyimides and the so-called ladder polymers — specifically designed for high-temperature applications. However, it has also been possible to modify polymers to improve their thermal stability and hence extend then-range of utility. A few examples of condensation polymers illustrate this point. [Pg.133]

The organotin halide chosen for most of this study was dibutyltin dichloride because of its low cost relative to other organotin halides and the observation from previous studies that other polymers, namely cellulose, and polyvinyl alcohol, which were modified through condensation with dibutyltin dichloride, showed good activity against a number of fungi tested. ... [Pg.235]

Resins. Most of the coalings for plastics formulated today utilize a flexi-biUzed polyol resin system that generally fits into one of two categories an acrylic or modified acrylic polyol or a condensation polymer (polyester, polyurethane, a combination of both through a physical blend, or modified resins that fall within the condensation polymer regime). [Pg.260]

We have been active 1n modifying commercially available vinyl polymers which contain polar groups utilizing techniques developed by us through condensation reactions of Lewis diacids with Lewis dibases. Most of these modifications can be depicted in general as follows... [Pg.60]

Turning the lactic acid into a polymer involves a chemical process called condensation, whereby two lactic acid molecules are converted into one cyclic molecule called a lactide. This lactide is purified through vacuum distillation. A solvent-free melt process causes the ring-shaped lactide polymers to open and join end-to-end to form long chain polymers. A wide range of products that vary in molecular weight and crystallinity can be produced, allowing the PLA to be modified for a variety of applications. [Pg.20]

Synthesis of Polymers. Polyamic acid solutions were prepared by condensation of the aromatic anhydride and amine in N,N-dimethylacetamide (DMAc). Polyimide modified electrodes were made by casting or spin coating the precursor polyamic acid solution onto stainless steel or platinum substrates. Imidization was achieved by either heating the films to 400°C for 60 min or through a chemical dehydration process involving immersion in a 1 1 mixture of acetic anhydride and pyridine (6). BTDA-DAPI films were made by casting from a DMAc solution and heating to 100 C. [Pg.395]

The ideal approach to reducing volatile yield is to use an inherently stable matrix polymer and reference has already been made to the chemical structures that confer maximum thermal stability. Alternatively, there are additives which function in the condensed phase and modify the degradation pathway. Phosphorus-based additives, usually working through a phosphoric acid intermediate, are popular additives, particularly for polyurethanes. They act predominantly in the condensed phase, increasing char yield and reducing volatile production. [Pg.145]

Another early material, still in wide use, that formed polymer networks, was the alkyd resins. The alkyds are a group of resins which can be called oil-modified polyesters. These polymers are formed through the condensation and exchange reactions among polybasic acids, polyhydric alcohols, and fatty monobasic acids. Typical polybasic acids are phthalic acid anhydride, maleic anhydride, etc. The polyhydric alcohol may be glycerin, pentaerythritol, etc., while the fatty acids may originate in soy bean or linseed oil. A typical alkyd has the following structure ... [Pg.230]


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Condensation polymers

Modified condensation polymers

Modified condensation polymers polymer

Modified polymers

Modifying polymers

Polymer condensation polymers

Polymer modification modified through condensation

Polymers modifiers

Through polymers

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