Polyurethane rubber-poly methyl

By combining elastomeric and brittle glassy phases it is often possible to obtain improved properties over a range of temperature and frequency. However, relatively little attention has been given to fatigue in IPNs, and to energy absorption in polyurethane rubber/poly(methyl methacrylate) (PU/PMMA) systems. 

Poly(ethylene terephtlhalate) Phenol-formaldehyde Polyimide Polyisobutylene Poly(methyl methacrylate), acrylic Poly-4-methylpentene-1 Polyoxymethylene polyformaldehyde, acetal Polypropylene Polyphenylene ether Polyphenylene oxide Poly(phenylene sulphide) Poly(phenylene sulphone) Polystyrene Polysulfone Polytetrafluoroethylene Polyurethane Poly(vinyl acetate) Poly(vinyl alcohol) Poly(vinyl butyral) Poly(vinyl chloride) Poly(vinylidene chloride) Poly(vinylidene fluoride) Poly(vinyl formal) Polyvinylcarbazole Styrene Acrylonitrile Styrene butadiene rubber Styrene-butadiene-styrene Urea-formaldehyde Unsaturated polyester... 

PB PBI PBMA PBO PBT(H) PBTP PC PCHMA PCTFE PDAP PDMS PE PEHD PELD PEMD PEC PEEK PEG PEI PEK PEN PEO PES PET PF PI PIB PMA PMMA PMI PMP POB POM PP PPE PPP PPPE PPQ PPS PPSU PS PSU PTFE PTMT PU PUR Poly(n.butylene) Poly(benzimidazole) Poly(n.butyl methacrylate) Poly(benzoxazole) Poly(benzthiazole) Poly(butylene glycol terephthalate) Polycarbonate Poly(cyclohexyl methacrylate) Poly(chloro-trifluoro ethylene) Poly(diallyl phthalate) Poly(dimethyl siloxane) Polyethylene High density polyethylene Low density polyethylene Medium density polyethylene Chlorinated polyethylene Poly-ether-ether ketone poly(ethylene glycol) Poly-ether-imide Poly-ether ketone Poly(ethylene-2,6-naphthalene dicarboxylate) Poly(ethylene oxide) Poly-ether sulfone Poly(ethylene terephthalate) Phenol formaldehyde resin Polyimide Polyisobutylene Poly(methyl acrylate) Poly(methyl methacrylate) Poly(methacryl imide) Poly(methylpentene) Poly(hydroxy-benzoate) Polyoxymethylene = polyacetal = polyformaldehyde Polypropylene Poly (2,6-dimethyl-l,4-phenylene ether) = Poly(phenylene oxide) Polyp araphenylene Poly(2,6-diphenyl-l,4-phenylene ether) Poly(phenyl quinoxaline) Polyphenylene sulfide, polysulfide Polyphenylene sulfone Polystyrene Polysulfone Poly(tetrafluoroethylene) Poly(tetramethylene terephthalate) Polyurethane Polyurethane rubber... 

The development of plastics also reflects economic history. Restrictions on imported latex, wool, silk and other natural materials to Europe during the Second World War resulted in the rapid development of alternative synthetic plastics. Table 1 shows that between 1935 and 1945, many new polymers were introduced including polyethylene, polyamides, poly(methyl methacrylate), polyurethanes, poly(vinyl chloride) (PVC), silicones, epoxies, polytetrafluoro-ethylene and polystyrene. Polyethylene was incorporated into radar systems while PVC replaced the limited stocks of natural rubber as cable insulation. 

The commonly used biomedical polymer materials include Polytetrafluoroethene, polyurethane, polyvinyl chloride, silicone rubber, polypropylene, polysiloxane gel, poly methyl acrylate, chitin derivatives and Polymethylmethacrylate. 

Several workers have proposed new combinations of materials in an attempt to overcome wear. Studies involving polyimides, polyamide-imides, and poly-tetrafluoroethylene-filled polyoxymethylene demonstrated that although wear characteristics were good in dry conditions, the presence of lubricants (blood plasma, water) decreased the wear resistance. Results obtained with reinforcing materials such as carbon fibre and with an aluminium oxide ceramic ball used in conjunction with a polyethylene socket have been presented, Examples of other types of reconstructive surgery involving hard tissue replacement are the use of poly(methyl methacrylate) in chest wall reconstruction and repair of depressed skull fractures, the repair of major crano-orbital defects with the aid of a polyurethane-coated poly(ethylene terephthalate) mesh, and the use of silicone rubber in total finger joint and carpal bone replacement. 

FIG. 12-11. Relaxation spectra of various polymers reduced to corresponding states. Panel I (1) composite methacrylate polymers (2) polyisobutylene (3) polyhexene-1 (4) polyurethane rubber. Panel II (1) poly(vinyl acetate) (2) poly(methyl acrylate). Panel III (1) Hevea rubber. 

A Russian patent [179] claimed the application of this process to many polymers—poly(vinyl chloride), poly(vinylidene chloride), poly(methyl methacrylate), polystyrene, polymethacrylonitrile, fluoroethylene polymers, poly(vinyl acetate), polyamides, polyurethanes, polyesters, phenol-formaldehyde resins, and epoxy resins. The monomers used included acrylic and methacrylic acids, their esters, amides, vinyl acetate, and styrene. Attempts have also been made to apply this system to the preparation of block copolymers from natural rubber and vinyl monomers [180]. 

PANI, polyaniline MMT, montmorillonite PEO, poly(ethylene oxide) PI, polyisoprene PP, polypropylene MA, maleic anhydride PVDF, poly(vinylidene fluoride) PA6, nylon 6 PET, poly(ethylene terephthalate) PU, polyurethane PHA, poly(hydroxyalkanoate) PE, polyethylene PDMS, poly(dime-thylsiloxane) PLPVS, poly(vinylsilsesquioxanes) PLLA, poly(L-lactide) BR, butyl rubber PTT, poly(trimethylene terephthalate) PVME, poly(vinyl methyl ether) NR, natural rubber NBR, nitrile rubber. 

Fig. 35. Dissipation factor vs frequency for polar polymers at 25°C. A, Clear cast phenolic B, plasticized PVC C, poly(vinyl chloride-co-vinylidene chloride) (saran) D, unplasticized PVC E, poly(methyl methacrylate) G, poly(hexamethylene adipamide) (nylon) H, poly(2-chlorobutadiene) I, plasticized ethyl cellulose J, cast epoxy K, methyl silicone rubber L, polyurethane foam (d = 33 g/L) and M, 50% polystyrene-50% chlorinated biphenyl.

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. 

Santra RN et al. (1995) In-situ compatibilization of thermoplastic polyurethane and polydimethyl siloxane rubber by using ethylene methyl acrylate copolymer as a reactive polymeric compatibilizer. Adv Poly Technol 14(l) 59-66... 

Figure 1 Polymer interpretation chart. PAI, polyamideimide PC, polycarbonate UP, unsaturated polyester PDAP, diarylate phtalate resin VC-VAc, vinyl chloride-vinyl acetate copolymer PVAc, polyvinyl acetate PVFM, polyvinyl formal PUR, polyurethane PA, polyamide PMA, methacrylate ester polymer EVA, ethylene-vinyl acetate copolymer PF, phenol resin EP, epoxide resin PS, polystyrene ABS, acrylonitrile-butadiene-styrene copolymer PPO, polyphenylene oxide P-SULFONE, poly-sulfone PA, polyamide UF, urea resin CN, nitrocellulose PVA, polyvinyl acetate MC, methyl cellulose MF, melamine resin PAN, polyacrylonitrile PVC, polyvinyl chloride PVF, polyvinyl fluoride CR, polychloroprene CHR, polyepichlorohydrin SI, polymethylsiloxane POM, polyoxy-methylene PTFE, polytetrafluoroethylene MOD-PP, modified PP EPT, ethylene-propylene terpolymer EPR, ethylene-propylene rubber PI, polyisoprene BR, butyl rubber PMP, poly(4-methyl pentene-1) PE, poly(ethylene) PB, poly(butene-l). (Adapted from Ref. 22, p. 50.)...

Interest continues in the binding of heparin to polymers in an attempt to produce non-thrombogenic surfaces. This has been the aim in the use of glutaralde-hyde-protein complexes as coatings for latex rubber and polyurethanes. Glutaraldehyde has also been used to bind antibodies to partially hydrolysed polyamide surfaces for enzyme-linked radioassay techniques. One of the few examples of direct polymerization (as opposed to surface modification) in an attempt to produce polymers having improved compatibility involves the use of 2-methacryloyloxyethylphosphoryl choline in the formation of homopolymers and copolymers with methyl methacrylate. An isocyanato-urethane methacrylate has been synthesized from 2-hydroxyethyl methacrylate in connection with dental materials research in which the preparation of poly functional monomers for improvement of interfacial bonding with tooth tissue is a topic of some interest. 

Although not strictly the subject matter of this book, work is briefly reviewed next on the application of non mass spectrometric Py-GC methods in the determination of polymer structure. This information is inclnded in the hope, when necessary, that chemists will be able to adapt these methods by including a mass spectrometric detailed information on polymer structure acrylates [63, 105-107], rubbers [63, 108-110], PVC [63,111-115], aliphatic polyhydrazides [116], polyoxamides [116], polyamides [117], polyether imides [118], methacrylamide [119], aromatic aliphatic polyamides [117], polyurethanes [120], chitin graft poly(2-methyl 2-oxazolone) [121, 122], polyxylyl sulfide [123-126], epoxy resins [127], polyethylene oxalate [128], polytetrafluoroethylene [129], polyvinylidene chloride [129], polyepichlorohydrin, fluorinated ethylene-propylene copolymer [129], polyvinyl fluoride [129], polyvinylidene [129], fluoride [129], SBR copolymer [129] and styrene-isoprene copolymer [130]. 

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