Poly copolymer network

Byme et al. [124] have shown the possibility of creating imprinted polymer ordered micropattems, of a variety of shapes and dimensions, on polymer and silicon substrates using iniferters and photopolymerization. They applied this approach to the recognition of D-glucose using copolymer networks containing poly(ethylene glycol) and functional monomers such as acrylic acid, 2-hydro-xyethyl methacrylate, and acrylamide. 

To use this method for the preparation of imprinted colloids, Whitcombe et al. applied it during the shell preparation. They synthesized a copolymer network shell consisting of poly(EGDMA-co-cholesteryl (4-vinyl)phenyl carbonate) using a variety of different seed particles to build the polymer core [26]. The seed particles used were 30-45 nm in diameter and the imprinted p(EGDMA-co-CVPC) shell resulted to a thickness of about 15 nm (Fig. 3). The specific BET surface area of the core-shell particles was typically 80 m2 g... 

As in conventional glass-ionomers, the acidic component in resin-modified glass-ionomers is either poly(acrylic acid) or acrylic/maleic acid copolymer. In many brands, this polymer is simply blended with the monomer HEMA in aqueous solution. However, in certain brands, the polymeric acid is modified with side chains that allow it to participate in the addition polymerization process and thereby form a copolymer network with the HEMA. 

Figure 8.28. Dilatometric data for poly(vinyl trichloroacetate)/poly-(methyl methacrylate) AB cross-linked copolymers. Networks IV and V show two second-order transitions, while network VI shows only one transition. (Bamford et aL, 1971.)...

Zotzmann, J., Behl, M., Feng, Y., and Lendlein, A. (2010) Copolymer networks based on poly(co-pentadeca-lactone) and poly(e-caprolactone) segments as a versatile triple-shape polymer system. Advanced Functional Materials, 20, 3583-3594. 

If DCPD is copolymerized with other NBE-type monomers like 2-norbornene-5-methylester (NBE-ME), using 4 as catalyst, the Tg of the so obtained copolymers decrease linearly with the NBE-ME content from 145°C (pure DCPD) to 57°C (pure NBE-ME) and the swelling in toluene increases from 100 to >900%, pointing to a sharp decrease in the crosslink density. This and similar experiments with other comonomers suggest a random incorporation of the comonomer into the poly(DCPD) network. 

Yanul, R A., Kirsh, Y. E., Verbrugghe, S., Goethals, E. J. and Du Prez, F. E. (2001) Thermoresponsive properties of poly(N-vinylcaprolactam)-poly(ethylene oxide) aqueous systems Solutions and block copolymer networks , Macromolecular Chemistry and Physics, 202,1700-1709. 

Most commonly, aliphatic polyester or poly (propylene oxide) prepolymers are used and often have functionalities >2, thus giving rise to the formation of segmented copolymer networks. 

Kalakkunnath, S., Kalika, D. S., Lin, H., and Freeman, B. D. (2(X)5). Segmental relaxation characteristics of crosslinked poly(ethylene oxide) copolymer networks. Macromolecules 38, 9679. Kalakkurmath, S., Kalika, D. S., Lin, H., and Freeman, B. D. (2(X)6). Viscoelastic characteristics of U.V. polymerized poly(ethylene glycol) diacrylate networks with varying extents of ciosslinking. 

In Chapters 3 and 11 reference was made to thermoplastic elastomers of the triblock type. The most well known consist of a block of butadiene units joined at each end to a block of styrene units. At room temperature the styrene blocks congregate into glassy domains which act effectively to link the butadiene segments into a rubbery network. Above the Tg of the polystyrene these domains disappear and the polymer begins to flow like a thermoplastic. Because of the relatively low Tg of the short polystyrene blocks such rubbers have very limited heat resistance. Whilst in principle it may be possible to use end-blocks with a higher Tg an alternative approach is to use a block copolymer in which one of the blocks is capable of crystallisation and with a well above room temperature. Using what may be considered to be an extension of the chemical technology of poly(ethylene terephthalate) this approach has led to the availability of thermoplastic polyester elastomers (Hytrel—Du Pont Amitel—Akzo). 

See also PBT degradation structure and properties of, 44-46 synthesis of, 106, 191 Polycaprolactam (PCA), 530, 541 Poly(e-caprolactone) (CAPA, PCL), 28, 42, 86. See also PCL degradation OH-terminated, 98-99 Polycaprolactones, 213 Poly(carbo[dimethyl]silane)s, 450, 451 Polycarbonate glycols, 207 Polycarbonate-polysulfone block copolymer, 360 Polycarbonates, 213 chemical structure of, 5 Polycarbosilanes, 450-456 Poly(chlorocarbosilanes), 454 Polycondensations, 57, 100 Poly(l,4-cyclohexylenedimethylene terephthalate) (PCT), 25 Polydimethyl siloxanes, 4 Poly(dioxanone) (PDO), 27 Poly (4,4 -dipheny lpheny lpho sphine oxide) (PAPO), 347 Polydispersity, 57 Polydispersity index, 444 Poly(D-lactic acid) (PDLA), 41 Poly(DL-lactic acid) (PDLLA), 42 Polyester amides, 18 Polyester-based networks, 58-60 Polyester carbonates, 18 Polyester-ether block copolymers, 20 Polyester-ethers, 26... 

Synthesis of comb (regular graft) copolymers having a PDMS backbone and polyethylene oxide) teeth was reported 344). These copolymers were obtained by the reaction of poly(hydrogen,methyl)siloxane and monohydroxy-terminated polyethylene oxide) in benzene or toluene solution using triethylamine as catalyst. All the polymers obtained were reported to be liquids at room temperature. The copolymers were then thermally crosslinked at 150 °C. Conductivities of the lithium salts of the copolymers and the networks were determined. 

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