A Polymerization Degree Of Pvac Rapid Determination Method Research And Application

Polyvinyl Alcohol (PVA) and Polyvinyl Acetate (PVAc) belong to the high polymers. PVAc is one of the middle products in PVA producing process. The average molecular weights (or the average polymerization degree) of PVA and PVAc reflect their property as polymers and are the most basic structure parameters for the high polymers. In the polymer industries, average polymerization degree is the most important controlling index for producing process and product quality. In this paper, polymerization degree, viscosity and concentration of PVA and PVAc had been investigated. The relationships between polymerization degree, viscosity and concentration had been studied to provide aggressive helps to the company production. The better results were reached under the guidance of the research in the actual production, which shows that these research results have an important and actual application value in the industry.The main research results are followed as:1. A kind of quick and accurate measurement method of polymerization degree for PVAc had been found. Comparing with traditional method, the method shorten the measurement time of polymerization degree of PVAc, cutting the time from 5-6 hours to no more than 1 hour, which outstandingly satisfied the needs of the fast-accurate analytical characteristics in actual producing control. It was proved that the method had the aggressive function to the PVA production.2. Main influence factors of the PVA viscosity were investigated through experiments, and a mathematic model of the relationship between polymerization degree and viscosity of PVA was set for PVA of The YUNWEI STOCK.3. The relationship between viscosity and concentration of PVA was investigated and a suggestion was put forward to modify the national standard (which named GB 12010.3-89). In this way, an improvement and more reasonable viscosity measurement of PVA was suggested.4. A calculation method of the mixed viscosity for PVA with difference viscosity was studied, and a viscosity formula for mixtures of PVA was determined by experiments.