Synthesis and characterization of the high-ortho thermoplastic phenolic resin in the absence of catalysts
ZHANG Wenfa, YIN Yonggang, LIU Chunling*, DONG Wensheng
(Key Laboratory of Applied Surface and Colloid Chemistry of Ministry of Education,School of Chemistry and Chemical Engineering,Shaanxi Normal University, Xi′an 710119, Shaanxi, China)
Abstract:
The high-ortho thermoplastic phenolic resin was synthesized by using formaldehyde and excessive phenol as reactants in the absence of catalysts under high pressure and high temperature conditions. The influences of various parameters such as the ratio of raw materials, reaction temperature and pressure on the properties of the resultant phenolic resin were investigated. Various methods such as the soften point measuments, nuclear magnetic resonance spectroscopy (NMR), differential scanning calorimetry-thermogravimetric (DSC-TG) analysis were used to characterized the structure and performance of the resin.The results showed that the higher the water content in the raw material,the better the product stability was.When the reaction was carried out at 210 ℃ for 1.5 h,the polycondensation reaction was completed.
KeyWords:
high-ortho phenolic resin; curing performance; polycondensation reaction
