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Unsaturated spiro ortho carbonate

Finally, the unsaturated spiro ortho carbonates were been shown to undergo double ring opening in a free radical polymerization to introduce a carbonate group in the backbone of an addition polymer (19). [Pg.153]

Figure 2. Densities of the monomeric unsaturated spiro ortho carbonate and related polyoxycarbonate vs. temperature... Figure 2. Densities of the monomeric unsaturated spiro ortho carbonate and related polyoxycarbonate vs. temperature...
By a very similar synthetic scheme, other unsaturated spiro ortho carbonates were prepared. [Pg.54]

A potential use of this monomer is in the area of dental fillings in which a slurry containing 20% of very fine crystals of the unsaturated spiro ortho carbonate I in 60% of the adduct of methacrylic acid to bisphenol-A diglycidyl ether (Bis-GMA) plus 20% trimethylolpropane trimethacrylate produces on polymerization a material with essentially no change in volume. An investigation of a bubble test on tooth enamel showed that this copolymer had nearly double the adhesion to the tooth structure that the base resin had without the addition of the unsaturated spiro ortho carbonate. The copolymer also had improved impact strength but yet essentially the same modulus, and filled composites appeared to have somewhat improved abrasion resistance. [Pg.44]

By a very similar synthetic scheme, other unsaturated spiro ortho carbonates were prepared. Bulk polymerization or solution polymerization in chlorobenzene gave soluble polymer if the reaction was stopped at low conversion. [Pg.46]

The chemistry of a wide variety of unsaturateo spiro ortho carbonates and unsaturated spiro ortho esters have been discussed in detail previously (14,19,24,27-X). They not only are useful for monomers that expaiu on polymerization Qa,32-21) but are useful as dental filling materials (38), for the syntHesTs of oligomers capped with hydroxyl groups, pro( ction of biodegradable polymers, and enhancement of thermal stability of copolymers (39-45) ... [Pg.58]


See other pages where Unsaturated spiro ortho carbonate is mentioned: [Pg.47]    [Pg.47]    [Pg.57]   


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Spiro ortho carbonate

Unsaturated carbon

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