Polyarylates PAr

These polyesters, [-0-t )-C(CH3)2-( )-C02- )-C0-] (Tg 188 °C and HDT = 120-175 °C), were introduced in 1974. The commercial resins include U-polymer , Ardel , Durel , and Aryloit . Their advantages include transparency, good weatherability, and high HDT. PAr has been blended with nearly all resins, including ABS, EPDM, ionomers, LCP, PA, PB, PBl, PBT, PC, PEI, PEK, PET, phenoxy, PMB, PS, PPE, PPS, etc. Three types of PAr blends are of particular importance - those with polyesters, PEST, polyamides, PA, and polyphenylenesulfide, PPS. A summary of PAr blends is provided in Table 1.75. 

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Polyarylate (PAR)-b-PSt and PAR-b-PMMA for compatibiiizers are described 135,39,40). The addition of PAR-b-PSt (1-10 parts) to 100 parts of a blend of PAR-PSt (7w-3w) resulted in improvement of the tensile and flexural modulus (Fig. 4), and PSt dispersed particles were diminished from 1-5 microns to an order that is undetectable by SEM, indicating the excellent, compatibilizing effect of the block copolymer. The alloy thus formed exert the characteristic of PAR, an engineering plastic, as well as easy processability of PSt. Addition of PAR-b-PMMA (3 or 8 parts) to 100 parts of a blend of PAR-polyvinylidenefluoride (PVDF) (7w-3w) resulted in improved microdispersed state of PVDF due to compatibility of PMMA with PVDF, while segregation of PVDF onto the surface was controlled. 

Poly(2,2 -bis(l,4-phenylene)propane terephthalate-co -isophthalate) (polyarylate, PAR)... 

PAR. See Polyarylate (PAR) para-Cresol (p-cresol), 384-385 para-Cresol novolac resin, 425 Paraformaldehyde, 377, 398 Para-para methylene linkages, 393, 395,... 

Polyarylate (PAR), 22 Poly(arylene), optically active, 518-519 Poly(arylene ether ether ketone) (PEEK), 327... 

Polyarylates (PAr) are wholly aromatic polyesters derived from aromatic dicarboxylic acids and diphenols or their derivatives. They are amorphous in nature with good injection moldability. Figure 7 shows the typical formula structure of PAr. 

A whole series of high-performance polyester LCPs was introduced in 1985. They were assembled from p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid. Polyarylates (PARs) - amorphous phenolic esters derived from aromatic dicarboxylic acids (mixtures of terephthalic acid and isophthalic acid) and biphenols such as bisphenol A - are produced by Amoco (Ardel ), Celanese (Durel ) and DuPont (Arylon ) at a volume of approx. 2000 t/a. 

The term HT-thermoplastics is used for polymers, which in the absence of fillers, have a continuous-use temperature above approx. 200 °C. In contrast, standard plastics, such as PVC, polyethylene or polystyrene, have continuous-use temperatures of the order of 100 °C. In addition to their high temperature stability, HT-thermoplastics, in general, possess good resistance to chemicals and usually also low flammability. Among the most important HT-thermoplastics are polyphenylene sulfides (PPS), polysul-fones (PSU), polyether sulfones (PES), polyether imides (PEI), polyetherether ketones (PEEK) and polyarylates (PAR). 

For the proposed technique community verification, namely, the equation (29), the authors [24] used the literary data for polymer-solvent 16 pairs in reference to polymers of different kinds polyearbonate (PC), poly(methyl methacrylate) (PMMA), poly(vinyl ehloride) (PVC), polydimethylsiloxane (PDMS), polyarylate (PAr) and polystirene (PS) [5, 17, 18, 20]. The solubility parameters 6 of the indieated polymers is accepted according to the data [16, 32]. The eomparison of ealeulated according to the Eqs. (4) and (29) Devalues for these polymer-solvent pairs... 

The polyarylate (PAr) on the basis of phenolphthaleine and dichlora-nhydride of isophthalic acid (F-1) [5] were used. Tetrachloroethane, N, N-dimethylformamide, tetrahydrofuran and 1,4-dioxane were used as solvents. As it is known through Ref [89], the reason of changes in the structure of a macromolecular coil in diluted solution with temperature variation can be both the effects of long-range interaction (excluded voliune effects) and the effects of short-range interaction leading to the specific influence... 

The authors [105] used amorphous glassy polymers PMMA, polycarbonate (PC) and polyarylate (PAr). The necessary for further evaluations shear modulus values G were obtained according to Young s modulus E experimental values with the formula using [88] ... 

The experimental studies of reactions in polymers confirmed the correctness of the approach [18] as a whole and the Eq. (106) of Chapter 2 and Eq. (6) in particular [19]. The authors [20, 21] elaborated the dimension d determination technique and verified its correctness on the example of two polymers melt polyarylate (PAr) and block-copolymer polyarylat-earylenesulfoxide (PAASO). These polymers polycondensation mode and their main characteristics (glass transition temperature T, mean weight molecular weight M and thermooxidative degradation rate k) are adduced in Table 3. 

For kH calculation the authors [10] supposed that all the used in work polymers (polyarylates (PAr), poly(vinyl chloride) (PVC), poly(methyl methacrylate) (PMMA), polysulfone (PSF) and polycarbonate (PC)) had the same molecular weight MM = 5 x 105. 

This paper is devoted to a study of the physical blends and transreacted copolymer products of a polyarylate (PAr) and bis-phenol-A polycarbonate (PC). Both polymers are amorphous thermoplastics of relatively high glass transition temperatures. 

The polyarylate (PAr) used is composed of bisphenol-A (BPA) units with a mixture of terephthaloyl (TP) and isophthaloyl (IP) units (molar ratio BPA TP IP = 2 1 1). PAr is a commercial product of Union Carbide Co., with the trade name of RDEL-DIOO. 

The presence of liquids or vapors in the enviromnent of a polymeric component affects the response to external mechanical forces. Thus, for instance polyarylate (Par) under uniaxial extension exhibits exclusively shear yielding without crazing. However, exposure to organic vapor (methy-lethyl ketone) results in crystallization, embrittlement, and conversion of the response to deformation from shear yielding to crazing [42]. 

Durel Polyarylate, PAr, and PAr/PBT blends, glass fiber reinforced or not Hoechst Celanese Corp. 

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