Institute of Macromolecular Chemistry “P.Poni” Aleea Gr.Ghica Voda Nr.41
A, Iasi-6600, Romania
A new class of polyhydroxyesterimides has been
synthesized by the Diels-Alder (DA) reaction between dihydroxyesters of resinic
acids (RA) and dihydroxyesters of carboxyphenylmaleimide (CPMI).
Dihydroxyesters of RA and CPMI have been synthesized by reaction between of
epoxy resins (diglycidyl ether of bisphenol A, diglycidyl ether of hydroquinone
and diglycidyl of aniline) and RA and CPMI. These monomers of AA, AB and BB
type were then allowed to polymerise under DA reactions. The obtained polymers
are solid, brittle, soluble in high and medium polar solvents and present good
thermal properties.
Key Words: Diels-Alder
polymerisation, resinic acids, carboxyphenylmaleimide
1. Introduction
Because nonrenewable raw materials
such as petroleum, coal and natural gas as intermediates for polymer industry
will be disappearing in the near future, development of renewable and
environmentally friendly resources (from forest and agriculture products)
appears a necessary step.
Rosin is a natural product obtained from the exudates (oleoresin) of trees, especially conifers. Its essential constituents are the abietic and levopimaric acids. These resin acids can react on their carboxylic acid group by esterification, by reduction, by decarboxylation etc. and also on their double bonds to form Diels-Alder adducts. These derivatives have been used as intermediates for polymers synthesis such as formaldehyde resins, allylic polymers, unsaturated and saturated polyesters, epoxy resins, alchydic resins, paper sizing agents etc. /1-16/. A number of polyamides, polyesterimides and polyimides based on levopimaric acid maleic anhydride Diels-Alder adduct and on levopimaric acid acrylic acid Diels-Alder adduct have been reported. These polymers were obtained by polycondensation of dicarboxylic Diels-Alder adduct with internal preformatted imide group with diols or diamine or by Diels –Alder polymerization of resinic derivatives with bismaleimide /17-24, 25/.
The aim of the present study is the synthesis and characterization of polyhydroxyimides obtained from Diels-Alder polymerization of AA, BB, AB monomers type, which contain in their structure hydrophenantrene moieties.