Preparation And Application Of Vegetable Oil Foamable Polyurethane Adhesive

The price of petroleum products is increasing dramatically nowadays with the decreasing of petroleum resource. Hence using natural renewable resources such as vegetable oil as a chemical raw material to produce polyurethane adhesive has better environmental ,economic and social benefits,especially reduces the dependence on petrol in the world.In this thesis, the technological conditions for production of a series of one component foamable polyurethane adhesive from castor oil, polyether polyols, polyester polyols and PAPI were studied detailedly. In addition, factors on preparation of the prepolymer of polyurethane, product properties and storage stability were researched. The results showed that isocyanate index was 2.8~3.0, castor oil was 40% of total polios(w/w), prepolyer catalyst was T-12, curing catalyst were Morpholine and LX-1, the solvent were ethyl acetate and dichloromethane, reaction time was 3h at 70~80℃. The products reached the requirements of building material industry.Moreover, the synthesis of the polyols which were prepared by the additional reaction of acidic oil with maleic anhydride first, then the esterification reaction with diethylene glycol and the polyols application in foamable polyurethane adhesive were studied, and the technical conditions of the impact of product performance was discussed in the article. The conclusions were drawn as follows: n(acidic oil): n(maleic anhydride): n(diethylene glycol) was1:1:3.3, the time span of esterization in normal pressure was 10 h; the temperature for esterization under a vacuum of 0.005 MPa was 240℃, and the hydroxyl value of acidic oil polyol was between 200~300 mgKOH/g. After study the effects of every influential factor on foamable polyurethane adhesive, it has manifested that the performance of mono-component foamable adhesive will be bettered in the condition that acidic oil polyols is 30% total polyols(w/w), isocyanate index at least was 3.5, the contents of catalyst was 0.05% of total polyols(w/w), and solvent was methylene dichloride; the double-component adhesive produced in the following condition frothed quickly, performed excellently and cheaper with well-distributed bubble and high sticky strength: 100 parts acidic oil polyols, 1 part catalyst, 1 part water, 30 parts methylene dichloride, 1 part stabilizing agent with hydroxide radical component, PAPI as firming agent.