PC/PMMA/PVAc

Fig. 22 MDSC scans of the (a) first, and (b) second heating runs recorded for the 1 1 1 molar PC/PMMA/PVAc coalesced blend. The sample was held for 3 min at 170°C after the first heating [35]...

Fig. 23 DSC thermogram of the coprecipitated PC/PMMA/PVAc blend, first heating scan...

DSC scans recorded for PC/PMMA/PVAc blends obtained by solvent-casting and coprecipitation evidenced four distinct glass-transitions, one for each component polymer and one indicating that some of the PMMA and PVAc chains were mixing (see Fig. 23). 

We also observed that the PC chains possess a preferred ability to form inclusion compounds with y-CD in solution, when competing with PMMA and PVAc. From the XH NMR spectrum of the coalesced 1 1 1 PC/PMMA/PVAc blend (not shown), the molar ratio of PC PMMA PVAc was determined to actually be 1.6 1 1.4 compared to the initial molar ratio of 1 24 24, respectively, used in solution to form their common y-CD-IC. Despite the initial 1 24 24 PC PMMA PVAc molar ratio in solution, the PC component in the coalesced PC/PMMA/PVAc blend is still prevalent over the PMMA and PVAc components, which indicates that there may be additional factors that govern the inclusion process from a multiguest system. We believe that this very strong preference of the host y-CD molecules for PC chains, rather than the other two possible guests, is due to their different hydrophobicities. Although the final molar ratio of the coalesced ternary blend can be somewhat controlled by modifying the initial molar ratio of polymers in their common solution, our eventual aim is to be able to adjust, as desired, the constituent polymer ratios in coalesced ternary blends. 

A particularly important application of ATR-FTIR is the in situ study of swelling of polymer O-rings and seals under extreme conditions. In situ ATR-FllR also allows the study of the behaviour of polymers subjected to supercritical fluids [197]. Reliable measurements of the solubilities of CO2 or any other IR-absorbing gas in polymers at various temperatures and pressures are possible. Kazarian et al. [198,199] have examined the interaction of SCCO2 with a variety of polymers (PMMA, PVAc, PC, PET, PS, PE) by means of in situ ATR-ETIR. The technique is useful for monitoring supercritical fluid processing. 

Uyar et al. recently demonstrated with the support of DPMS that both the phase structures and the properties of polymer blends can be modified by processing with cyclodextrines (CDs). In fact, thermal stabilities and thermal degradation mechanisms of mixed blends of polycarbonate/PMMA (PC/PMMA), PC/PVAc and PMMA/... 

Figure 15. Influence of the Polyester Yellow dye film absorbance and polymer binder material on the marking threshold energy. PnBMA = poly(n-butyl methacrylate) PiBMA = poly(isobutyl methacrylate) PS = polystyrene PsBMA = poly (sec-butyl methacrylate) PVB = polyvinylbutyl PMMA = polymethyl methacrylate PVAC = polyvinylacetate, S-iBMA = poly(styrene-co-isobutyl methacrylate), PC = polycarbonate S-AN — poly(styrene-co-...

Eq. (5) in conjunction with Eqs. (8) and (9) have, so far, provided adequate representation of experimental isotherms6 32, which are characterized by an initial con vex-upward portion but tend to become linear at high pressures. Values of K, K2 and s0 have been deduced by appropriate curve-fitting procedures for a wide variety of polymer-gas systems. Among the polymers involved in recent studies of this kind, one may cite polyethylene terephthalate (PET) l2 I4), polycarbonate (PC) 19 22,27), a polyimide l6,17), polymethyl and polyethyl methacrylates (PMMA and PEMA)l8), polyacrylonitrile (PAN)15), a copolyester 26), a polysulphone 23), polyphenylene oxide (PPO)25), polystyrene (PS) 27 28), polyvinyl acetate 29) and chloride 32) (PVAc and PVC), ethyl cellulose 24) (EC) and cellulose acetate (CA) 30,3I>. A considerable number of gases have been used as penetrants, notably He, Ar, N2, C02, S02 and light hydrocarbons. 

PC PE PES PET PF PFA PI PMMA PP PPO PS PSO PTFE PTMT PU PVA PVAC PVC PVDC PVDF PVF TFE SAN SI TP TPX UF UHMWPE UPVC Polycarbonate Polyethylene Polyether sulfone Polyethylene terephthalate Phenol-formaldehyde Polyfluoro alkoxy Polyimide Polymethyl methacrylate Polypropylene Polyphenylene oxide Polystyrene Polysulfone Polytetrafluoroethylene Polytetramethylene terephthalate (thermoplastic polyester) Polyurethane Polyvinyl alcohol Polyvinyl acetate Polyvinyl chloride Polyvinyl idene chloride Polyvinylidene fluoride Polyvinyl fluoride Polytelrafluoroethylene Styrene-acrylonitrile Silicone Thermoplastic Elastomers Polymethylpentene Urea formaldehyde Ultrahigh-molecular-weight polyethylene Unplasticized polyvinyl chloride... 

In another study, it was successfully reported an intimate ternary blend system of poly(carbonate) (PC)/poly(methyl methacrylate ) (PMMA)/poly (vinyl acetate) (PVAc) obtained by the simultaneous coalescence of the three guest polymers from their common y-cyclodextrin (y-CD) inclusion complex (IC). The thermal transitions and the homogeneity of the coalesced ternary blend were studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) [50]... 

Acrylic polymers are recognized for their miscibility with a variety of polymers, viz. miscibility of PMA with PVAc [Kem, 1957]. PMMA is miscible with standard PC at T < LCST - 140°C. The miscibility range can be greatly increased by modifying the PC chain ends (LCST < 300°C) [Kambour, 1988]. Demixing PMMA/PC blends by the spinodal decomposition mechanism generated alloys with excellent mechanical properties [Kyu, 1990]. 

PF (Novolac)/PS, SAN, PEA, PVAc, PEMA, PMMA, PMPS, PC, or PVME Novolac (PF) blends frequency shifts in CO vibration from 1,774 to 1,752 cm due to hydrogen bonding in miscible blends 9... 

PMMA PC, MSAN, EPA, poly(meth)acrylates, PE, NC, PPG, PVAc, PVC, PVC-V Ac, CPVC, PVDF, etc. 

PE, PC, PET, PS, i-PS, PVP, PMMA, PTEE PVAc, PVC Toluene, CCI4, CHCI3, xylene, decalin, EtOH, H2O, MeOH The casting solvent has a pronounced infiuence upon the friction coefficient which may ctmfer cithCT ductile or brittle failure. Good solvent gtaierally tends to promote brittle mode of failine with little temperatine dependence. Friction measurements (Briscoe and Smith 1983)... 

C, O PVAL, poly(vinyl ether), poly(vinyl acetal)s, polyketones, epoxy resins, phenol resins, PMMA, PC, PVAC, polyester, cellulose and derivatives... 

Melt processing has been used also for polymer and polymer blend/silica nanocomposites. In particular, extensive studies are reported for PP [228], PP-based copolymer [229], PE [230], PE-based copolymer [231,232], PS [233-235], PMMA [234,235], PC [234], PC-based copolymer [236], polyethylene naphthalate (PEN) [237], perfluoropolymer [238], PET [239-241], PA [242], polyvinyl acetate (PVAc) [243], co-polyetherester [244], styrene-butadiene rubber [245,246], ethylene vinyl acetate (EVA) [247], PET/PS [248], PLEA [249], and many others. 

Besides water-soluble polymers, more synthetic polymers are insoluble in water and should be dissolved in organic solvent for electrospinning, such as polylactic-co-glycolic acid (PLLA), PCL, polybutylene succinate-co-butylene terephthalate (PBST), polyhydroxyalkanoates (PHA), polybutylene succinate (PBS), PAN, poly-sulfone (PSF), polyimide (PI), polyethylene-co-vinyl alcohol (PEVA), PU, polypyrrole (PPy), polyoxymethylene (POM), PS, polymethyl methacrylate (PMMA), PVC, polyvinylidene fluoride (PVDF), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT), poly A-vinylcarbazole (PVK), polymeta-phenylene isophthalamide (PMIA), polyethylene terephthalate (PET), polycarbonate (PC), polybenzimidazole (PBI), polymer vinyl acetate (PVAc), polyvinyl butyral (PVB), and polyethylene-co-vinyl acetate (PEV). 

In the last twenty years, many polymers have been used to make polymer nanocomposites. Thermoplastic polymers include nylon, polyaniline (PANI), " poly(s-caprolactone), polycarbonate (PC), polyether ether ketone (PEEK), polyethylene (PE), poly(ethyl acrylate) (PEA), polyisoprene (PI), polylactide (PLA), poly(methyl methacrylate) (PMMA), " polypropylene (PP), polypyrrole (PPy)," polystyrene (ps)/ i i7,27,30,49-64 poiy inyl acetate) (PVAc), poly(vinyl alcohol) (PVA), poly(vinyl chloride) (PVC) and thermoplastic polyurethane (TPU), and thermosets include Bakelite, butadiene rubber, epoxy,polydimethylsiloxane (PDMS), polyurethane (PU), styrene-butadiene rubber (SBR) and unsaturated polyester resin. 

Basic polymer poly(vinyl pyridine) (PVP) and a hydrophobic stabilizer PTFE, PVDF, PVDF-HFP, PS, PBD, PVDC, PMMA, PVAI, PVAc, PPE, PEEK, PET, PBT PC, PBI, PDMS, PANI... 

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