Study On The Preparation Of Cross-linking Hydroxypropyl Starch

Glass fiber is the major breakthrough in the field of material in 20 th century. Its special properties make it play an important role in some key areas, such as aerospace, electronic information industry. China is a big producer of glass fiber, but the research of manufacture is seriously lagging behind. Thus, the glass fiber production technology in China is in a higher degree of import dependence.High amylose starch modification is an important part of fiber glass sizing agent. It has many advantages and gradually become a popular sizing agent especially for the electronic fabric. The advantages of modified high amylose starch include non-toxic, easy to clean, low decomposition temperature and so on. It has become a hot spot in the research of sizing agent. This article optimized the process parameters, and analyzed the performance of the product.In this paper, we used high amylose starch as raw material, propylene oxide as etherification agent, sodium hydroxide and glycol as catalyst. The process parameters of the reaction were optimized. The main parameters include etherification agent dosage, catalyst dosage, reaction temperature, and time. Through the comparison of the degree of substitution, transmittance, gelatinization temperature, various parameters are optimized. The experimental results show that temperature increasing can accelerate the reaction speed. But the temperature should be control to avoid gelatinization. Sodium hydroxide can catalyze etherification reaction effectively, but excessive sodium hydroxide had no obvious effect. Polyethylene glycol also can improve the reaction efficiency, but excessive polyethylene glycol would reduce the degree of substitution. The amount of etherification agent also can effectively improve the degree of substitution, but the reaction efficiency decreased.Through the investigation of the amount of etherification, reaction temperature, reaction time, we determined the best conditions of etherification reaction.Cross-linking hydroxypropyl starch were prepared, by etherification and cross-linking in order. We measured and analyzed various performance, such as gelatinization temperature, solubility, swelling degree, transparency, viscosity and the stability of viscosity. Cross-linking hydroxypropyl starch got an adaptive gelatinization temperature, high solubility, low swelling degree, good transparency, low viscosity, and stabile viscosity in different temperature and pH. These features are beneficial to the using in glass fiber industry as a good sizing agent.