Tetramethyl bisphenol

Rotational-echo double resonance NMR Tetramethyl bisphenol A polycarbonate Tetrachlorophthalic dimethyl ester Wiliams, Landel, Ferry... 

In order to investigate the molecular motions involved in this transition and, in particular, the nature of the associated cooperativity, it is interesting to consider not only BPA-PC, but also tetramethyl bisphenol A polycarbonate, TMBPA-PC, (Fig. 25) as well as copolymers of BPA and TMBPA carbonates, and compatible blends of BPA-PC and TMBPA-PC. 

Methyl methacrylate-co-N-methyl glutarimide copolymer Bisphenol A polycarbonate Tetramethyl bisphenol A polycarbonate Aryl-aliphatic copolyamides... 

In order to investigate the effect of a methyl substitution of the phenyl hydrogen in ortho position to the carbonate group, tetramethyl bisphenol A polycarbonate (TMBPA-PC), whose the chemical structure is shown in Fig. 66b, has also been considered. In the case of TMBPA-PC, the secondary fi transition happens at 50 °C, at 1 Hz (Fig. 67), in such a way that it allows one to examine the consequences of such a large shift of the fi transition on the mechanical properties. 

Investigation of the mechanical properties of bisphenol A polycarbonate (BPA-PC) and tetramethyl bisphenol A polycarbonate (TMBPA-PC) has led to... 

The telechelica,(i -bis(2,6-dimethylphenol)-poly(2,6-dimethylphenyl-ene oxide) (PP0-20H) [174-182] is of interest as a precursor in the synthesis of block copolymers [175] and thermally reactive oligomers [179]. The synthesis has been accomplished by five methods. The first synthetic method was the reaction of a low molecular weight PPO with one phenol chain end with 3,3, 5,5 -tetramethyl-l,4-diphenoquinone. This reaction occurred by a radical mechanism [174]. The second method was the electrophilic condensation of the phenyl chain ends of two PPO-OH molecules with formaldehyde [177,178], The third method consists of the oxidative copolymerization of 2,6-dimethylphenol with 2,2 -di(4-hydroxy-3,5-di-methylphenyl)propane [176-178]. This reaction proceeds by a radical mechanism. A fourth method was the phase transfer-catalyzed polymerization of 4-bromo-2,6-dimethylphenol in the presence of 2,2-di(4-hy-droxy-3,5-dimethylphenyl)propane [181]. This reaction proceeded by a radical-anion mechanism. The fifth method developed was the oxidative coupling polymerization of 2,6-dimethylphenol (DMP) in the presence of tetramethyl bisphenol-A (TMBPA) [Eq. (57)] [182],... 

The observation that Bib is more exothermic than Bz3 is not surprising when one considers the fact that blends of tetramethyl bisphenol-A polycarbonate with polystyrene are miscible while blends of bisphenol-A polycarbonate with polystyrene are immiscible (43 ). Apparently, substitution of methyl groups on the aromatic rings in the backbones of these materials enhances miscibility with the styrene repeat unit. The observation that Biz is also exothermic is quite surprising, considering the similarity of the trimethyl and dimethyl ether units. Using regular solution approximations, one could... 

Bisphenol A Bisphenol AP Tetramethyl bisphenol A Bisphenol E /. Bisphenol P... 

FIGURE 5.2. Representative electropherograms for three of the experiments of a Box-Behnken design and corresponding CRF (chromatographic response function) values. Used to optimize a separation of Bisphenols E, A, AP, and P, and Tetramethyl bisphenol A. Extracted from Reference 42. 

Felhofer et al. (46) reported an application describing the separation of five bisphenols (bisphenol E, bisphenol A, bisphenol AP, tetramethyl bisphenol A, and bisphenol P) by MEKC. It has been well established that bisphenols can reach the environment, and also the human body (47). Bisphenols are widely employed in the manufacture of plastics, especially those used in food and beverage packages, baby bottles, and water supply pipes. In this study, a univariate approach was first developed using a BGE composed of borate, SDS, and acetonitrile. The goal was to achieve the best separation of the... 

Bisphenol A, bisphenol E, bishphenol AP, tetramethyl bisphenol A, bisphenol P... 

The simplest method for the synthesis of m-brominated phenolics is the bromination of o- and p-substituted phenolics. As shown in the following equations, mesitol was brominated to give 3-5 dibromomesitol (8). The o-substituted tetramethyl bisphenol gave tri- and tetra-brominated compounds (9). Similar substitution occurs with the o-substituted tetramethyl bisphenol ethane (10). 

PS is miscible with several polymers, viz. polyphenyleneether (PPE), polyvinylmethylether (PVME), poly-2-chlorostyrene (PCS), polymethylstyrene (PMS), polycarbonate of tetramethyl bisphenol-A (TMPC), co-polycarbonate of bisphenol-A and tetramethyl bisphenol-A, polycyclohexyl acrylate (PCHA), polyethylmethacrylate (PEMA), poly-n-propyl methacrylate (PPMA), polycyclohexyl methacrylate (PCHMA), copolymers of cyclohexyl methacrylate and methyl methacrylate, bromobenzylated- or sulfonated-PPE, etc. Other miscible blends are listed in Appendix 2. 

Abbreviations for the polymeric units in Table 2.10 (C H )- - phenyl ring, a-MS - alpha-methyl styrene, AN, acrylonitrile, BMA - butylmethacrylate, CHMA - cyclohexylmethacrylate. Cl - caprolactone, C(VC) - unit of chlorinated PVC, DNS - 2,4-dini-trostyrene-co-styrene, DTC -2,2-dimethyltrimethylenecarbonate, HFPC - hexafluoro bisphenol-A polycarbonate, MA - maleic anhydride, MMA - methylmethacrylate, PAr - unit of polyarylate, Phenoxy - unit of polyhydroxy ether of bisphenol-A, PPE - unit of poly(2,6-dimethyl-1,4-phenylene ether), S - styrene, TMPAr - unit of tetramethyl bisphenol-A polyarylate, TMPC - unit of tetramethyl bisphenol-A polycarbonate, VAc - vinyl acetate, VC - vinyl chloride, VCVAc90 - VC-co-VAc copolymer with 90 wt% VC, VME - vinylmethylether. 

As indicated in Fig. 23.1, a sample consists of a rigid glass indenter and an elastomer substrate of crosslinked poly(dimethyl siloxane) (PDMS), which are both coated with the polymer layers of interest. These layers include a semicrystalline layer of poly(ethylene oxide) (PEO) sandwiched between glassy polymer layers of poly(tetramethyl bisphenol A polycarbonate) (TMPC). These polymers will be described in more detail within this section along with the steps that were taken to select these polymers for the study of a glassy/semicrystalline interface. 

Kim, S. and Liu, J. 2001. Molecular modelling of bisphenol-A polycarbonate and tetramethyl bisphenol-A polycarbonate. Korea Polym. J. 9 129-142. 

Polyethersulfone Polyarylether sulfone Tetramethyl bisphenol-A poiysuifone Poiysuifone and polysulfones with pendent groups... 

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