Studies On Reduced-Color Technics Of Polymerized Rosin

Rosin is a kind of renewable natural resin and important chemical material. There are abundant rosin resource in Guangxi province, Guangxi province had produced 180,000 tons rosin one year . To further process the rosin can improve the using area ahd economic value of rosin products. Polymorized rosin is one important kind of process rosin. It has the advantages of high softening point, high acid value, good capability of anti-oxidation and high mucosity. Polymerized rosin is good used in high-grade printing ink, adhesives and dope,etc. However, there are many disadvantages on the producing process of polymerized rosin,the quality and technical datas are up to scratch or can't fit the demands, the yield is low, affected the marking and using. So improving the process of polymerized rosin, can make the best use of rosin resource, improve economic benefit of factories, and has important meaning on rosin industry and technology progress.In this article, we use rosin as material, study to improve the rosin polymerized process, especially study on improving the color of products. We have test the catalyst, solvent, reaction temperature & time, sedimentation & separation, abstersion,etc., which how to affect the rosin polymerized reaction and product's quality. We test some new techniques such as using mixed-acid catalyst, adjusting the reaction speed, temperature and sedimentation temperature, had chosen the best technical parameters. We had emphasized on reducing the color of polymerized rosin, the results indicated that seven kinds of chemical antioxidant all had reduced-color effects, KYA& KYG were good reduced-color reagents, had got obvious effects. The accession amount is only l~2% of rosin weight. The optimization technical conditions was: using toluene as solvent, thick sulfuric acid plus AA1 as mixed-acid catalyst, reaction temperature was 35 C, reaction time was 4 hours, sedimentation temperature was 10 ~ 15 C , and added 1 ~ 2 % KYA & KYG as reduced-color reagents. Using the technical process of this article, we can produce better polymerized rosin , which quality datas are like these: softening point is 136~145 C, Gaderna color-grade is 6~7#( accorring to rosin color-grade, it is up to Special-grade-one grade). Dimers content had grown form 25~35% to 50~65%. The acid value is higher, which can reach 140~ 150 mgKOH/g or higher, the yield can reach to 80~88%. The other quality datas are up to grade. These polymerized rosin products are up to the national industry standard ZBB72008-89, and better than it. This arcticle can provide experimental datas to middling-experiment and industry producing.