Tetramethyl bisphenol A polycarbonate TMPC

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. 

The study of blends of PC with PCL (M =15,000, M =46,700) and other polyesters was extended to tetramethyl bisphenol-A polycarbonate (TMPC) 16 by Fernandes et al. [86]. The sample of TMPC used (r j.epl 29) had Tg=193.5 °C and Tj 280 °C. Samples were cast from toluene or dichloromethane and, when relatively dry from solvent, residual solvent was removed under vacuum at 80 °C (dichloromethane) or 110 °C (toluene). 

Blends of tetramethyl bisphenol-A polycarbonate, TMPC with AMS-AN copolymers were prepared by precipitation from THF into methanol. Miscible regions were found for copolymers of AMS-AN with a range of AN compositions from 4.0-16.5 wt%. Phase separation temperatures were determined by examination of the glass... 

The first positron annihilation lifetime (PAL) measurements on polymer blends were conducted by Jean et al. [9], who investigated the free volume properties of (i) a miscible blend, namely tetramethyl-bisphenol A polycarbonate (TMPC) and polystyrene (PS) and (ii) an immiscible blend, namely bisphenol A polycarbonate (PC) and PS. It was observed that TMPC formed a miscible blend with PS as it had larger fractional free volume cavities than PC. For the miscible blend, the free volume showed negative deviation from the linear additivity rule (Eq. (27.19)), whereas for immiscible blend it was observed that the free volume, as detected by o-Ps lifetime as a function of composition, was complicated due to the presence of... 

The miscibility profile of aliphatic polyesters is similar (not surprising) to poly(e-caprolac-tone). The phase behavior of cellulose acetate proprionate (CAP) with ahphatic polyesters based on C2 to C8 straight chain diols with glutaric acid was investigated by Buchanan et al. [224]. Miscibility was observed with C2 to C6 diols and partial miscibility with the C8 diol based aliphatic polyesters. Although CAP is typically amorphous (unblended), crystallization was observed by plasticization of the lower Tg polyesters. The crystallization rate of the aliphatic polyesters was suppressed by addition of CAP. Aliphatic polyesters with CH2/COO ratios of 2 to 5 have been shown to be miscible with Bisphenol A polycarbonate (PC) [225] and miscible with tetramethyl Bisphenol A polycarbonate (TMPC) with CH2/COO ratios of 5 to 10 [226]. Aliphatic polyesters also showed a miscibility window with phenoxy (PHE) with the volume fraction of the aliphatic carbon in the polyester of between 0.7 and 0.9 [227]. 

Polystyrene is immiscible with PC however, tetramethyl Bisphenol A polycarbonate (TMPC) is miscible and exhibits lest behavior [439]. The CPMAS NMR analysis gave indication of homogeneity of the TMPC/PS blend at the level of a few nanometers [440], consistent with SANS data of 2 nm [441]. Styrene-MMA copolymers are immiscible with PC, but miscible with TMPC [442]. Miscibility maps for SMMA copolymer blends with hexafluorobisphenol A-tetramethyl bisphenol A copolymers show areas of single phase behavior. TMPC miscibility windows with a series of styrene copolymers (SAN, SMA, styrene-allyl alcohol (SAAl)) have been reported [443 ]. Miscibility of the copolymers with TMPC was maintained for SAN (0-13 wt% AN), SMA (0-8 wt% MA) and SAAl (0-19 wt% aUyl alcohol). Dimethyl bisphenol A-tetramethyl bisphenol A PC copolymer blends with SMMA yielded miscibility with SMMA (< 37 wt%) and PC copolymer with > 60 wt% tetramethyl bisphenol A content [444]. Tetramethyl Bisphenol S polycarbonate is not miscible with polystyrene, but is miscible with styrene-acrylonitrile copolymers (range estimated to be 14 to 42 wt% AN) [445]. Miscibility was also observed with an a-methyl styrene-acrylonitrile copolymer (31 wt% AN). 

One relevant example is taken from studies of thick films ( 100 tm) of tetramethyl bisphenol A polycarbonate (TMPC) and PS mixtures (Figures 39-41). The films of a near-critical mixture TMPC/PS (50/50, w/w) were casted on glass slides from tetrahydrofuran (THF) (common solvent for... 

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. 

Bulk spinodal decomposition in TMPC/PS [TMPC = poly(tetramethyl-Bisphenol-A-polycarbonate)] films was also studied by Cabral et ol. [151] using AFM. These authors were able to show that the topography observed by AFM is related to the spinodal morphology, although the periodicity of the structure determined by AFM appears to be larger than expected from LS measurements. Since the AFM structure factor is obtained by Fourier transform of an image of a cross-section (2D) whereas the LS data are 3D Fourier transform of the spinodal structure, such a discrepancy between AFM and LS results is not surprising. 

One of the main goals of experimental studies carried out on polymer blends is to resolve the dynamics of the individual components. For dielectric measurements this can be achieved when one of components has a high dipole moment, for example, PVME, poly(chlorostyrene), or poly(tetramethyl-Bisphenol-A-polycarbon-ate) (TMPC) [163,164], compared to the second polymer, for example, polystyrene. 

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. 

TMPC Polycarbonate of tetramethyl bisphenol-A TPE Thermoplastic elastomer TPU Thermoplastic polyurethane TPV Thermoplastic vulcanizate... 

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