| In this paper, it was reviewed on the applications of synthesis of epoxy resin andpolyurethane from turpentine, and the development and progress of epoxy resin andpolyurethane modified with eath other. A novel idea of synthesis, crosslinking reaction andproperties of alicyclolic epoxy resin with endocyclic structure from turpentine or dipentene andits polyol derivatives was provided. The main contents and conclusions of this paper are listedas follows:1. An alicyclolic epoxy resin with endocyclic structure, hydrogenated terpinene-maleic estertype epoxy (HTME), was synthesized from the raw material hydrogenated terpinene-maleicanhydride (HTMA). The best synthesis conditions were confirmed by studying about theeffects on synthesis reaction of ratio of material, reaction temperature and time, dosage ofcatalyst, the dosage and concentration of alkali and the type of solvents. In the stage ofesterification reaction, when reacted at about 100℃for longer than 2h, the esterification cantake place more completely at the epichlorohydrin (ECH) /HTMA mol ratio of 10/1 and byadding catalyst in amount from 1% to 1.5% by weight based on the weight of HTMA. At thering-closing reaction stage, when using ECH as solvent and solid alkali at the OH/HTMA molratio of 1.8～1.9, more desirable effects can be obtained by adding solid alkali in batches in 2hat 50℃and after finishing it maintaining at 70℃for additional 2h. The epoxy resin wastransparent pale yellow liquid with epoxy value 0.35～0.39 mol/100g, viscosity at 50℃1.7Pa.S and acid value＜0.5 mg/g determined by chemical analysis methods, and its chemicalstructure was also characterized by FT-IR and NMR spectra.2. It is widely known that the excellent properties of epoxy resin could not be obtained untilcured with curing agents, such as amine and anhydride. In this paper, the activity of curingreaction between HTME and methyl hexahydrophthalic anhydride (MeHHPA) wasinvestigated by means of DSC and gelatin time determination. The enthalpy of the curingreaction is 153.5J/g. The curing behaviors of HTME/MeHHPA system were studied byqualitative analysis of FT-IR spectrum and quantitative analysis of curing degreedetermination. The mechanic properties of HTME cured with MeHHPA were compared withthat of TME and epoxy resin 6101 at the same condition and found that all of them were aboutthe same. 3. To improving the toughness of epoxy resin with polyurethane, three kinds of polyols weresynthesized by reacting HTME with active hydrogen containing compounds, such asdiethylamine(DEA), N-methylethanolamine(MEA) and diethanolamine(DeA). They can beused in place of the commonly used polyols, such as polyether glycols and polyester polyols, toprepare two-component polyurethanes. The best synthesis conditions were confirmed bystudying about the effects on synthesis reaction of the ratio of material, reaction temperatureand time, the type and the dosage of solvents. When reacted at 60～70℃for about 2h, betterquality products can be obtained by using ethanol as solvent which desirably accounts for 40%by weight based on the weight of reactants. The chemical structures of the polyols from HTMEwere characterized by chemical analysis methods and FT-IR spectra.4. The effects of catalyst,temperature and polarity of solvents on reactivity of the threepolyols crosslinked with polyisocyanate were examined by viscosity method. It was found thatthe reactions could be catalyzed by the tertiary amine groups included in the polyols. And thecrosslinking processes of the reactions between the polyols and polyisocyanate werecharacterized with FT-IR spectra by observing the change of -N=C=O stretch peaks. Themechanical, water-resistant and chemicals-resistant properties of the crosslinked products wereevaluated according to standard tests.The results showed the crosslinked products which can becalled epoxy-urethane polymers had excellent impact strength, flexibility and water-resistant,chemicals-resistant properties. It is indicated that these epoxy-urethane polymers have madeepoxy resin and polyurethane modified with each other successfully.The creative achievements of this work are summarized as follows:1. An alicyclolic epoxy resin with endocyclic structure, HTME, has been synthesized fromturpentine, one of the renewable resource of forest products. In contrast to the commonly usedbisphenol A epoxy resin, HTME has excellent weatherability property, because it containssaturated endocyclic structure instead of the structure of the benzene ring in bisphenol A epoxyresin. And this synthetic method of HTME is superior with uncomplicated technology and highyield.2. The normally methods to modify epoxy resin with polyurethane are the EP/PUinterpenetrating polymer networks, the processes of which are quite complex and difficult tocontrol. In this paper polyols based on HTME have been synthesized to crosslink withpolyisocyanate in place of the commonly used polyols. The crosslinked systems which can becalled epoxy-urethane polymers combine the rigidity and weatherability of the saturated terpinene alicyclic epoxy resin(HTME) with the flexibility and tenacity of the polyurethaneperfectly.The purpose of the present study was to provide favorable theoretical basis for the synthesismethod, toughening technology of epoxy resin, and the application of the renewable resourceof forest products on preparation for special polymers.
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