| A resole-type phenol-formaldehyde resin containing large number of hydromethyl groups was synthesized from phenol and aqueous formaldehyde using ammonia as catalyst. Modified phenol-formaldehyde resins were developed from polyvinyl butyral. a new general phenolic-HNBR hot vulcanization adhesive is prepared from he synthesis modified phenolic resin together with NBR and corresponding additives. This resin-rubber compound adhesive can be used for hot vulcanization cementation between different content of acrylonitrile of NBR and HNBR and phosphating metal skeleton,and the performance was evaluated. This thesis mainly include the following content:1.The synthesis of modified phenolic-formaldehyde resinsDiscussed the influence of different phenol, maldehyde and poly (vinyl alcohol) of different quality ratio, reaction temperature and time conditions on the structure and performance of the synthesis acetal modified phenolic resin.The product structure was characterized by FT-IR. With various kinds of chemical analysis and test method,such as free of phenol, free aldehyde, viscosity, solid content and peel strength index of acetal modified phenolic resin was determinated. Best technology: the phenol: formaldehyde=6:7, heating up to 80℃-85℃in slow continuous react for three hours, after cooling the polyvinyl butyral is mixed by the quality ratio about one to ten (1:10), react for 1 hour at 50℃-55℃, reduced pressure after dehydration, can get free formaldehyde content is 0.3771%, free of phenol content is 0.4403%, the alcohol-soluble acetal modification of phenolic resin of solid content 52% can be made after dehydration by reducing the pressure adjusting. This modified phenolic resin adhesives peel strength can reach 10.5 KN/m above in 160℃curing 15 minutes.2. The enlargement test research for Modified phenol-formaldehyde resins On the basis of laboratory experiment, the enlargement test research has been proceeded successfully for Modified phenol-formaldehyde resins which were develop from polyvinyl butyral, the optimal process conditions:dosage ratio of raw materials,catalysts and reaction temperature,the amount of acetal respectively ere 6:8,1.00,95℃,0.4, This modified phenolic resin adhesives peel strength can reach 7.59 KN/m in this condition, which lay a good foundation for the industrialization of the products.3. Preparation of modified phenolic resin-NBR composie adhesiveThe character of the preparation in this paper are the steps. The high acrylonitrile content NBR was being plasticated on the open mill for 1-3minutes to the mooney viscosity 60-70. Then tackified resin,inorganic fillers,coupling agent,antiager and vulcanizer were added one by one. After a while, MIBK was added and we can get rubber mucilage. Modified phenolic resin was mixed in the end and the modified phenolic-NBR composite adhesive was made. We researched bonding results of the NBR (butyronitrile rubber) with different contents of AN (acrylonitrile) and carbon steel metal frame by this adhesives. The test results showed modified phenolic-NBR composite adhesive can get a good quality and cheap price. |
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