Study On The Modification Of Phenolic Resin Applied To Friction Materials

The modification of phenolic resin by Tung oil and linseed oil is studied. First phenol and Tung oil/linseed oil react in the acid condition, and then react with formaldehyde to thermosetting phenolic resin in the alkalinity condition. First trials is carried on in the aspects of the activator of synthesis,the ratio of raw materials.the recaction temperature,the reaction time and the temperature and time of dehydration. And then conclude the best modification technics.The best modification technics of phenolic resin by Tung oil is, phenol:Tung oil: hydrochloric acid = 1:0.5:0.0015(ratio of mass); the activator of synthesis of Tung oil and phenol is hydrochloric acid, the recaction temperature is 100-110°C, the reaction time is 2-3h; the reaction activator of the produce of Tung oil and phenol and formaldehyde is ammonia, the dosage is phenol:ammonia(25%)=1:0.06(ratio of mol), the reaction temperature is 100-110°C, the reaction time is 2h, the temperature of dehydration is 50°C, the time of dehydration is 30min.The best modification technics of phenolic resin by linseed oil is, phenol: linseed oil:p-methyl benzene sulfonic acid=1:0.5:0.01(ratio of mass); the activator of synthesis of linseed oil and phenol is p-methyl benzene sulfonic acid, the reaction temperature is about 140°C, the reaction time is 3-4h; the reaction activator of the produce of linseed oil and phenol and formaldehyde is ammonia, the dosage is phenol:ammonia(25%)=1:0.06(ratio of mol), the reaction temperature is 100-110°C, the reaction time is 2h, the temperature of dehydration is 50°C, the time of dehydration is 30min.The structure of modified phenolic resin, modification mechanism and The structure character of thermosetting modified phenolic resin is analyzed by FT-IR . FT-IR indicates, the modification of phenolic resin by Tung oil and Unseed oil is only the reaction between Conjugate bond of Tung oil and non- Conjugate bond of linseed oil and vicinal, para-hydrogen of phenol, so thermosetting modified phenolic resin is synthesized. The solidification process and oxygenation decomposition process of modified pnenolic resin is analyzed by DSC and TG-DSC as to evaluate the heat stability. DSC indicats the solidification process of modified phenolic resin have three phases. It is mostly condensation reaction of methylol and break reaction of ether link. And hydroxyl of phenol, Tung oil and linseed oil do not react. TG-DSC indicates heat decomposition temperature and heat stability of modified resins are improved greatly...