Polyether, aliphatic aromatic

Various types of condensation polymers such as aromatic polysulfonates and polysulfides, aromatic polyethers, aliphatic and aromatic polysulfides, and carbon-carbon chain polymers of high molecular weights by the phase-transfer catalyzed polycondensation fi-om combinations of aromatic disulfonyl chlorides, phosphonic dichlorides, activated aromatic dichlorides, and aliphatic dihalides, withbisphenol, aliphatic and aromatic dithiols, and active ethylene compounds. The two-phase polycondensation was generally carried out in a water-immiscible organic solvent-aqueous alkaline solution system at room temperature. The method of polycondensation offers a highly versatile and convenient synthetic method for a variety of condensation polymers. 

Aliphatic diisocyanate/polyester diol Aliphatic diisooyanate/polyether diol Aromatic diisocyanate/polyester diol Aromatic diisooyanate/polyether diol... 

Phosphate esters are readily identified by the phosphate bands at 2700, 2300, 1250-1300, and 900-1100 cm The spectrum is adequate to detect aliphatic, aromatic, and polyether character, but is normally insufficient to discriminate among similar products (21). 

The tendency of aliphatic ethers toward oxidation requires the use of antioxidants such as hindered phenoHcs (eg, BHT), secondary aromatic amines, and phosphites. This is especially tme in polyether polyols used in making polyurethanes (PUR) because they may become discolored and the increase in acid number affects PUR production. The antioxidants also reduce oxidation during PUR production where the temperature could reach 230°C. A number of new antioxidant products and combinations have become available (115,120,124—139) (see Antioxidants). 

Polyester block copolymers can be defined as (AB) -type alternating multiblock copolymers composed of flexible aliphatic polyester or polyether blocks (A-type blocks) and rigid high-melting aromatic-aliphatic polyester blocks IB-type blocks) (Formula 2.2). 

F.D. Konstandakopoulou, K.G. Gravalos, and J.K. Kallitsis, Synthesis and characterization of processible aromatic-aliphatic polyethers with quinquephenyl segments in the main chain for light-emitting applications, Macromolecules, 31 5264-5271, 1998. 

Telechelic polymers rank among the oldest designed precursors. The position of reactive groups at the ends of a sequence of repeating units makes it possible to incorporate various chemical structures into the network (polyether, polyester, polyamide, aliphatic, cycloaliphatic or aromatic hydrocarbon, etc.). The cross-linking density can be controlled by the length of precursor chain and functionality of the crosslinker, by molar ratio of functional groups, or by addition of a monofunctional component. Formation of elastically inactive loops is usually weak. Typical polyurethane systems composed of a macromolecular triol and a diisocyanate are statistically simple and when different theories listed above are... 

Commercially available hyperbranched polymers are Polyglycerol (aliphatic polyether polyol) and Polyethylenimine (aliphatic polyamine) both from Hyperpolymers, Boltom (aliphatic polyesters) from Perstorp and Hybrane (aromatic polyester amide) from DSM. 

A manifold of dendrimers have been presented in the literature ranging from polyamidoamine, polyfpropylene imine), aromatic polyether and polyester, aliphatic polyether and polyester, polyalkane,polyphenylene, polysilane, and phosphorus dendrimers. Combinations of different backbones as well as architectural modifications have also been presented. For example, the incorporation of chirality in dendrimers, copolymers of linear blocks with dendrimer segments (dendrons), and block copolymers of different dendrons has been described. Numerous applications have been proposed for dendrimers such as biotemplates, liquid membranes, catalysts, or in medical applications. ... 

Hyperbranched polymers are formed by polymerization of AB,-monomers as first theoretically discussed by Flory. A wide variety of hyperbranched polymer structures such as aromatic polyethers and polyesters, aliphatic polyesters. polyphenylenes, and aromatic polyamides have been described in the literature. The structure of hyperbranched polymers allows some defects, i.e. the degree of branching (DB) is less than one. The synthesis of hyperbranched polymers can often be simplified compared to the one of dendrimers since it is not necessary to use protection/deprotection steps. The most common synthetic route follows a one-pot procedure " where AB,-monomers are condensated in the presence of a catalyst. Another method using a core molecule and an AB,-monomer has been described. ... 

We have previously synthesized a number of titanium polyethers of the following general structure (3,4). A variety of aromatic and aliphatic diols were successfully incorporated as the fundamental backbone units of the polyethers. These materials are insoluble and do not soften prior to thermal-induced degradation. 

Titanium-containing polyethers have been prepared by the reaction of dicyclopentadienyltitanium dichloride with aromatic and aliphatic diols via an interfacial and/or aqueous solution polycondensation technique (273). 

Physical properties are related to ester-segment structure and concentration in thermoplastic polyether-ester elastomers prepared hy melt transesterification of poly(tetra-methylene ether) glycol with various diols and aromatic diesters. Diols used were 1,4-benzenedimethanol, 1,4-cyclo-hexanedimethanol, and the linear, aliphatic a,m-diols from ethylene glycol to 1,10-decane-diol. Esters used were terephthalate, isophthalate, 4,4 -biphenyldicarboxylate, 2,6-naphthalenedicarboxylate, and m-terphenyl-4,4"-dicarboxyl-ate. Ester-segment structure was found to affect many copolymer properties including ease of synthesis, molecular weight obtained, crystallization rate, elastic recovery, and tensile and tear strengths. 

The pre-polymers typically contain at least two epoxy groups spaced with an aromatic or aliphatic backbone or even by a fragment of chain including other functionalities. The most commonly used resin from this class is probably formed from epichlorohydrin and bisphenol A or 4-[1-(4-hydroxy-phenyl)-isopropyl]phenol under basic conditions to give a polymeric diglycidyl polyether as shown below ... 

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