摘要
以多聚甲醛、苯酚为原料,草酸为催化剂合成了覆膜砂酚醛树脂。采用软化点和固化时间测试以及气相色谱、凝胶渗透色谱和红外光谱对草酸用量和酚与醛物质的量比对树脂性能的影响进行了研究,并将其覆膜砂制品的性能与市售的高强度酚醛树脂覆膜砂进行了对比。结果表明:草酸用量为苯酚质量的1%,苯酚和甲醛的物质的量比为1∶0.7时,合成的树脂与市售高强度覆膜砂酚醛树脂的分子质量和分子质量分布,以及树脂的软化点、聚合速度、流动度等性能较为接近,制作的覆膜砂的冷弯强度和冷拉强度分别达到6.9 MPa和3.4 MPa,与市售品指标相当。
The phenolic resin for coated sand was synthesized by using paraformaldehyde and phenol as raw materials and oxalic acid as catalyst. The softening point and curing time tests as well as gas chromatography,gel permeation chromatography and infrared spectroscopy were used to study the effect of the oxalic acid amount and the molar ratio of phenol to aldehyde on the properties of the resin. And the performance of its coated sand products were compared with the commercially available high-strength phenolic resin coated sand. The results showed that the molecular weight,molecular mass distribution,softening point,polymerization rate,fluidity and other properties of the synthesized resin were relatively close to the commercially available high-strength coated sand phenolic resin,when the amount of oxalic acid was1 % by mass of phenol and the ratio of the amount of phenol to formaldehyde was 1 ∶ 0. 7. the cold flexural strength and cold tensile strength of the coated sand were 6. 9 MPa and 3. 4 MPa,respectively,which were equivalent to the performance of commercial product.
作者
李露
曹欢玲
Li LU;CAO Huan-ling(School of Engineering, Zhejiang A &F University, Hangzhou 311300, China)
出处
《热固性树脂》
CAS
CSCD
北大核心
2019年第2期42-45,共4页
Thermosetting Resin
关键词
酚醛树脂
多聚甲醛
覆膜砂
草酸
phenolic resin
paraformaldehyde
coated sand
oxalic acid