Modification Of Potato Starch And Its Application In Humidity-Sensitive Coatings

With the technological development and the improvement of living standards, the requirements of interior decoration are more highly. The safety, comfortable of indoor environment are the goal of people. The energy saving, resource saving, pollution-free are the development direction of coatings. The purpose of coating is not only the protection and decorative, but also the ecological, intelligent. Starch coating is prepared with modified-starch, which could reduce costs and improve the environmentally friendly performance of coatings. The potato planting area and output of our country are No. 1 in the world. China is the one of the world's largest producer of potato. And Gansu province is one of the important producing area of potato. The resource of potato starch is rich. Applied to high-end functionality of interior wall paint, is the one of direction of deep processing of potatoes.In this thesis, the grafted potato starch emulsion and room temperature self-crosslinking emulsion of potato starch were prepared. They were applied in humidity-sensitive coatings, to obtain environmentally friendly coatings. In this thesis, on the basis of the discusses of the modified starch (eg. physical modification and chemical modification) and its application (eg. paper industry, daily chemical industry, textile industry, petroleum industry, water treatment, food, building materials, printing and dyeing, leather and many other fields ), the following work were reported.1) The potato starch graft emulsion was prepared by potassium persulfate as initiator, potato starch graft skeleton, butyl acrylate (BA) and methyl methacrylate (MMA) as monomer for graft polymerization. The grafting efficiency and the monomer conversion rate were studied in different reaction conditions. The potato starch graft emulsion was also applied in humidity-sensitive coatings with other porous layers of pigment and filler mixture. The performance of humidity was measured. There were no volatile organic solvents. And potato starch is a natural edible ingredient. The potato starch graft emulsion humidity-sensitive coating was a green coating with environmental security, non-toxic.2) The room temperature self-crosslinking potato graft emulsion prepared by potassium persulfate as initiator, diacetone acrylamide (DAAM), butyl acrylate (BA) and methyl methacrylate (MMA) as monomer for graft polymerization. The grafting, grafting efficiency, the monomer conversion rate were studied in different reaction conditions. The room temperature self-crosslinking potato starch graft emulsion could crosslinked with dihydrazide (ADH) at room temperature to improve the properties of emulsion. The crosslinked latex was applied in humidity-sensitive coatings with other porous layers of pigment and filler mixture. The performance of humidity was measured. The basic performance of room temperature cross-linked potato starch graft emulsion humidity-sensitive coatings was up to the national standards. Which show it could be used as interior coatings. And it could be also applied in interior humidity with good humidity-sensitive performance.3) The microporous starch was prepared throughα-amylase. It was applied in styrene-acrylic emulsion humidity-sensitive coatings as filler. The basic performance of it was up to the national standards. Which shows it could be also applied in interior humidity with good humidity-sensitive performance.