INDEX Condensation polymers

Polymers formed from two or more monomers such as condensation polymers and copolymers, as well as homopolymers are indexed at each inverted monomer name with the modifying term polymer with followed by the other monomer names in uninverted alphabetical order. The preferential listing for identical heading parents is in the order (1) maximum number of substituents (2) lowest locants for substituents (3) maximum number of occurrences of index heading parent and (4) earliest index position of the index heading. Examples are ... 

Phenolic, (I), and naphtholic, (II), condensation polymers containing cyclopentane were previously prepared by Sue et al. (1). These materials were subsequently epoxidized with epichlorohydrin and used in electronic devices as ICs and Lumen solubility indexes (LSIs). In a subsequent investigation by Abe et al. (2) novolak resins functionalized with thiophene, (III), were prepared and used as adhesives. 

A polymerization that provides a transition into a discussion of gelation is the condensation of an excess of A-B with a small amount of an /-functional monomer, R-A/, that contains / equivalent functional groups of Type A, but no functional groups of Type B.[3 Linear chains are obtained when / is 1 or 2, but multichain condensation polymers are produced when/>2. At high conversion the polydispersity index depends only on/. 

The weight-average molar mass for linear condensation polymers also diverges as the extent of reaction p—> 1 (see Fig. 1.19). The polydispersity index of the linear condensation polymers,... 

Stacy in 1985 was able to determine molecular weights of PPS by light scattering of solutions above 200 C and used the values to calibrate molecular weight distributions determined by gel permeation chromatography above 200°C. Heterogeneity index (M /M ) for PPS is near 1.7, less than the value of 2.0 expected of condensation polymers. The difference is the absence of a low molecular weight tail in PPS. 

Kuran et al. [60] polymerized neopentyl carbonate using a catalyst prepared from water and diethylzinc and obtained a poly(neopentyl carbonate). The analysis by SEC yielded the average molar masses, namely Mr, = 3.0 kDa and = 6.3 kDa. The polydispersity index is close to 2, a typical value for a condensation polymer. The MALDI spectrum of the poly(neopentyl carbonate) displays almost 70 equally spaced peaks. The envelope is bell shaped. The abundances of chain with different sizes follows a Gaussian curve (sigma = 17) and centered at DP = 28. An accurate calculation was done by the authors using experimental peak intensities. Inserting these peak intensity values in Equations 45.1 and 45.2, they obtained Mr, = 3.5 kDa and M = 4.0 kDa. The polydispersity index associated with these values is 1.14. These three values are unacceptable since they are clearly affected by a large error. 

Polyurethanes are condensation polymers formed by step-growth polymerization in which the chain length of the polymer increases steadily as the reaction progresses. Two major routes of polymerization of polyurethanes are one-step and two-step synthesis methods. In one-step synthesis, the diisocyanate, polyol, and a chain extender are mixed together and allowed to react. In the two-step route, an oligomer or prepolymer synthesized from diisocyanate and polyol and the chain extender are allowed to react. The two-step route offers some advantages over the one-step route, such as a reduced polydispersity index and a higher extent of phase separation. 

Uses Solvent for removal of CO2 or H2S from gases, for recovery of aromatics from refinery streams surfactant Intennedlate for prep, of foam stabilizers, wetting agents, emulsifiers, and condensation polymers Properties Cl. colorless si. vise, liq. mild amine odor misc. with water, alcohols, aromatic hydrocarbons, ethyl ether m.w. 105.14 sp.gr. 1.0572 dens. 8.7 Ib/gal b.p. 221 C f.p. -12.5 C flash pt. (PMCC) 255 F ref. index 1.4 98% min. act. DilasoftRW [ClariantUK]... 

Table I shows a comparison of free film swell Index results as a function of crosslinker at a constant comonomer level (0.3 moles/kg of polymer). ABDA and AEP gave crosslinking performance Identical to a conventional crosslinker, BNMA. However, derivatives which cannot cycllze, either because the amide has an additional substituent, as In 13, or the chain connecting the amide to the blocked aldehyde Is too short, as In 14, did not exhibit efficient crosslinking. They also showed significant discoloration, presumably due to Increased aldol condensation relative to 1, 2, or BNMA.

What is the most probable value for the polydispersity index for (a) a monodisperse polymer and (b) a polydisperse polymer synthesized by a condensation technique ... 

Hydrogels and amphiphilic membranes Poly(carbophosphazenes) and poly(thiophosphazenes) New condensation syntheses NLO and high refractive index polymers Microencapsulation of mammalian cells (PCPP) Polyphosphazene polymer blends and IPN s Borazine derivatives Poly(phosphazophosphazenes)... 

The oxygen index increase was suggested to be due to a condensed phase mechanism and explained by taking into account the mechanism of thermal degradation of chloroparaffin and the interaction with the polymers. 

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