Multifunctional anhydride monomers

Anseth, K.S., Quick, D.J., 2001. Polymerizations of multifunctional anhydride monomers to form highly crosslinked degradable networks. Macromolecular Rapid Communications 22, 564-572. 

Poly(ethylene terephthalate) is a linear polyester obtained from the reaction of difunctional monomers. Branched or network polyesters are obtained if at least one of the reagents is tri- or multifunctional. This can be achieved either by the use of polyols such as glycerol in the case of saturated polyesters (glyptal) or by the use of unsaturated dicarboxyhc acids such as maleic anhydride in the ease of unsaturated polyester. In the preparation of glyptal, glycerol and phthalic anhydride reaet to form a viseous liquid initially, which on further reaction hardens as a result of network formation (Equation 2.31). 

Combinations of donor/acceptor systems, comprised of at least one multifunctional monomer, are actually capable of sustaining rapid fi ee-radical polymerization without external photoinitiators. Donor monomers can be vinyl ethers, N-vinylformamides, and N-vinylalkylamides. The acceptor monomers are maleic anhydride, N-arylmaleimides, N-alkylmaleimides, dialkyl maleates, and dialkyl fumarates. N-alkylmaleimides can participate in excited state hydrogen abstraction fi om diacrylates. The reaction proceeds either in the presence or in the absence of oxygen. ... 

Unsaturated low molecular weight (M between 1000 and 10000), often branched, used as macromonomers for synthesis of thermosets (polyester resins), or thermosetting materials by themselves (alkyd resins). They are prepared from several monomers, namely phthalic and maleic anhydrides, adipic acid, iso-phthalic acid, natural fatty acids or triglycerides, and a great variety of multifunctional alcohols. In a few special cases, they may be saturated and/or linear for use as macromonomers in the production of polyurethanes or other polymers. 

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