Preparation of Barium-phenolic Resin

2014/11/19

    Barium-phenolic resin, also known as phenolic- barium resin and barium glue, is curable phenolic resin at room temperature, which is prepared by polycondensation of phenol and formaldehyde under the action of the catalysis of barium hydroxide by means of decompression dehydration. Barium-phenolic preparation technics introduced by specialists: put melting phenol into reactor, then start stirring for 40-450℃ warming and add barium hydroxide. Heat up to 65～750℃ within 30 minutes and keep the temperature for 10-20 minutes until barium hydroxide completely dissolved. Then add formaldehyde solution, warning up and stirring until 850℃ within 20～30 minutes. The boiling temperature reaches 97～1000℃ because of heat release. Stir again after 10 minutes boiling reflux. Measure the muddy temperature after keeping about 60 minutes boiling reflux. When it reaches 40～500℃, release cold water immediately to reduce the temperature. When the inner temperature drop to 700℃ below, decompression dehydration shall be started with inner temperature kept at 500℃ and within 86.66～94.89kpa vacuum degree. Dehydration should be stopped when the dewatering amount is close to theoretical amount and sampling viscosity meets the requirement. Cool down to 400℃ then discharge. Barium-phenolic resin is soluble in ethyl alcohol and acetone and can be solidified at room temperature. Petroleum sulfonic acid, benzenesulfonic acid, paratoluensulfonyl chloride and so on are frequently-used as curing agent with usual dosage of 10% resin quality.