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Bonding polymethacrylates

Multiple H-bond Polymethacrylate 83 Organic Aromatic compounds... [Pg.59]

Ou DL, Gould GL (2005) Ormosil aerogels containing silicon bonded linear polymers, WO Pat. 2005068361 Ou DL, Gould GL, Stepanian CJ (2006) Ormosil aerogels containing silicon bonded polymethacrylate, WO... [Pg.633]

A number of polystyrene resins with significant residual double-bond contents have been used for grafting of polar hydrophilic polymethacrylate-polyethylene... [Pg.21]

The preparation of solids with covalently attached POM complexes is a serious and worthwhile research target because these materials might be expected to be rather stable to POM leaching in solutions. Many new materials of this type have been reported in the literature [16,49,74,137-143] however, catalytic studies on covalently boimd POMs still remain a rare event. In 1992, Judeinstein reported the first POM-polymer hybrid where a lacunary Keggin POM cluster was covalently linked to polystyrene or polymethacrylate backbone through Si-0 bonds [137]. This approach has been further developed by several research groups. [Pg.286]

After hydrolysis by 2N methanol solution of H2SO4, the product was neutralized with KOH to pH=5 and methanol evaporated. The dry residue was expected to be poly(allilamine), polymethacrylic acid, and K2SO4. Indeed, after extraction with anhydrous methanol and acetone, poly(allilamine) was identified by NMR and IR spectrometries. After evaporation, solvent from the methanol part of the extract insoluble in chloroform part was obtained. After esterification by diazomethane the product was identified as polyfmethyl methacrylate) on the basis of IR and H-NMR spectroscopy. IR spectroscopy was applied in order to examine the copolymerization of multimethacrylate (p-cresyl-formaldehyde oligomers with methacrylic groups) with st3rrene. It was found that double bond peak at 1650 cm disappeared during the process and it was absent in the product of polymerization. Polymerization and... [Pg.144]

Various methacrylic-styrene copolymers were prepared in which the reactivity of methacrylate monomers used in the first step decreases in the order MM A > BuMA > benzyl methacrylate. For instance, the bulk polymerization of MMA with such an aromatic azo compound proceeds via a living radical mechanism and the sterically crowded C-C(C6H5)3 terminal bond of polymethacrylate 37 can be cleaved thermally to produce a,co-diaromatic PMMA-h-PS block copolymers in 48-72% yield. [Pg.123]

The polymers evaluated are shown in Fig. 1. These twelve polymers cover typical types of organosilicon polymers, such as polysiloxane, ladder type polysiloxane, polysilane, polymethacrylate, polysilyl-styrene, and novolak. Polymers and were supplied by Shin-etsu Chemical Co., Ltd. Actually, polymer" 2 evaluated contains very small amount of vinylsiloxane for crosslinking by deep UV irradiation after coating, because the pure polysiloxane is a fluid at room temperature and is impossible to measure the etching depth. These polymers have Si-0 bonds in the main chain structure. Polymer was purchased from Shin Nisso Kako Co., Ltd. and was purified in house. Polymers 4 to 12 were synthesized in house. Polymers 1J and 12 have Si-0 bonds in side chain structure. Thermal Si02 1J was evaluated as a reference. ... [Pg.359]

Synthetic polymers can be prepared to contain chirality as is the case for cellulose and other natural polymers. Chirality can be introduced into the monomer before polymerization to yield the chiral polymer. Alternatively polymerization of an achiral monomer in the presence of some chiral catalyst yields the chiral polymer. Polymethacrylates exhibiting chirality due to single-handed helicity have been prepared via polymerization in the presence of a chiral catalyst. These materials are used in liquid chromatography primarily under low-pressure conditions and have shown good resolution for compounds capable of hydrogen-bond formation. [Pg.2160]

Instead of packed columns, monolithic (continuous bed), analytical, or capillary columns in the form of a rod with flow-through pores offer high porosity and improved permeability. Silica-based monolithic columns are generally prepared by gelation of a silica sol to a continuous sol-gel network, onto which a Cjg or another stationary phase is subsequently chemically bonded. Such columns provide comparable efficiency and sample capacity as conventional columns packed with 5-pm particle materials, but have three to five times lower flow resistance, thereby allowing higher flow rates and fast HPLC analyses. Rigid polyacrylamide, polyacrylate, polymethacrylate, or polystyrene monolithic columns are prepared by in sim polymerization. [Pg.1439]

Polymethacrylic acid, PMA, is composed of vinyl polymer backbone as with PAA molecules, but a carbons attached to carboxyl groups are bonded to methyl groups instead of hydrogen atoms. This rather hydrophobic poly-carboxylic acid shows a peculiar acid dissociation behavior. As is illustrated... [Pg.842]

Besides binary composites consisting of only one polymer component and the carbon nanotubes, the use of ternary or even quaternary mixtures was also found useful in some cases. There is, for instance, a composite of polymethacrylate with carbon nanotubes previously treated with polyvinyhdene fluoride (PVDF). It is obtained by melt blending. There may be no covalent bonding between nanotubes and methacrylate, the coating with the significantly less polar PVDF causes a good wettability by the matrix polymer. The PVDF obviously serves as composite mediator without which a separation of the other components might occur. [Pg.254]

Polymers for use in 193 nm lithography are co-, ter-, and tetra-polymers of 1) methacrylates, 2) norbornenes, 3) norbornene-maleic anhydride, 4) nor-bornene-sulfur dioxide, and 5) vinyl ether-maleic anhydride (Fig. 39). While 1), 3), 4), and 5) are prepared by radical polymerization, all-norbornene polymers 2) are synthesized by transition-metal-mediated addition polymerization [166-168].Norbornenes (Fig.40) are sluggish to undergo radical [168,169] and cationic [170] polymerizations. Their ring-opening metathesis polymerization (ROMP, Fig. 40) [ 171 ] has never produced worthy resist polymers. The C=C double bonds introduced in the ROMP polymer backbone must be hydrogenated to reduce the 193 nm absorption and the ROMP polymers tend to have low Tg. However, the major problem for the ROMP polymers was their unacceptable swelling in aqueous base development. While polymethacrylate systems contain etch-resistant alicyclic structures in the ester side chain, norbornene-based systems carry the alicyclic unit in the backbone. Essentially all the 193 nm re-... [Pg.79]


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See also in sourсe #XX -- [ Pg.66 ]




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