| Rosin and chitosan are very rich in China, and both of them are natural andrenewable resources. However, most of rosin is now exported as raw materialand the application of chitosan is limited due to its weak solubility, soexploitation of their deep processing products to raise their extra value is aresearch project worthy of carrying out deeply. In this paper, microwave-assistedsynthesis and application of the grafted copolymer from rosin and chitosan havebeen studied to exploit a new possible route for the deep processing of them.Firstly, a new method for synthesizing rosin allyl alcohol ester wasstudied. At first, in the presence of NaOH as catalyst, p-toluenesulfonic acidallyl alcohol ester was synthesized by O-acylation reaction of p-toluene sulfonylchloride with allyl alcohol, and then rosin allyl alcohol ester was synthesized bynucleophilic substitution reaction of sodium rosinate with the preparedp-toluenesulfonic acid allyl alcohol ester. By the single factor experimentation,the optimal conditions for the synthesis of p-toluenesulfonic acid allyl alcoholester were obtained to be as follows: n(allyl alcohol): n(p-toluene sulfonylchloride) 3:1, reaction time 3 h, reaction temperature 0℃and the yieldamounted to 89.5％. The optimal conditions for the synthesis of rosin allyl alcohol ester were found to be as follows: reaction temperature 40℃, reactiontime 2 h, solvent dosage 25 mL, n(sodium resinate): n(p-toluenesulfonic acidallyl alcohol ester) 1.3:1 and the yield was up to 75.4％. Rosin allyl alcoholester was analyzed and characterized by TLC, IR and GC-MS methods. Fromthe experiment results, it can be concluded that the new method put forwardabove had its advantages such as shortening reaction time, reducing reactiontemperature, and avoiding sub-reaction due to high temperature.Secondly, in thepresence of NaOH as catalyst, p-toluenesulfonicacid-[(2-acryloyloxy) ethyl] ester (TAEE) was synthesized by O-acylationreaction of p-toluene sulfonyl chloride (TsC1) with 2-hydroxyethyl acrylate(HEA), and then rosin-[(2-acryloyloxy) ethyl] ester (RAEE) was synthesized bynucleophilic substitution reaction of sodium resinate with the prepared TAEE.By the single factor experimentation, the optimal conditions for the synthesis ofTAEE were obtained to be as follows: n(HEA):n(TsC1) 5:1, reaction temperature0℃, reaction time 2h and theyield amounted to 83.9％. The optimal conditionsfor the synthesis of RAEE were found to be as follows: n(sodium rosinate):n(TAEE) 1.3:1(mol), reaction temperature 60℃, solvent dosage 30 mL,reaction time 3h and the yield was up to 72.6％. RAEE was analyzed andcharacterized by TLC, IR and GC-MS.Thirdly, chitosan (Cts) and RAEE were pre-radiated byγ- 60Co ray, thenthe grafted polymers (Cts-g-RAEE) was synthesized from Cts and the monomerof RAEE under the microwave irradiation and in the presence of potassium supersulphate as initiator. Various factors which may influence the graftingreaction were investigated. The optimal conditions were found to be as follows:under protection of N2, chitosan 0.5g, the microwave power 700W and 50mL of1％acetic acid solution, radiation dosage 300Gy, initiator 0.2g, microwavereaction temperature 50℃, microwave reaction time 2h, RAEE 4g. The graftedcopolymers were analyzed and characterized by means of IR, XRD, SEM, TGand DSC.Finaly, Cts and Cts-g-RAEE were used as carriers of fenoprofen calcium(FC), and their controlled release in gastric juice and in intestinal was studied.The results showed that the controlled release of fenoprofen calcium from thecarrier of Cts-g-RAEE is very good in artificial intestinal juice.
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