Molecular Weight of Water-Soluble Phenolic Resin on the Performance of Impregnated Filter Paper

Water-soluble phenolic resin was prepared through a multi-step feeding method.Effect of reaction time to the molecular weight and distribution of water-soluble phenolic resin was studied.The impact of molecular weight and distribution of water-soluble phenolic resin on the performances of impregnated filter paper was investigated.The results showed that molecular weight of water-soluble phenolic resin increases and its distribution becomes wide gradually as reaction time prolongs.Watersoluble phenolic resin of different molecular weight has little effect on the air permeability,the average and largest pore diameter of impregnated filter paper,while the thickness of impregnated filter paper decreases with the increases of molecular weight of phenolic resin.The strengthened filter paper's tensile strength,breaking elongation,breaking power and burst strength increase gradually while stiffness diminishes as the molecular weight of water-soluble phenolic resin increases.