竹材液化物酚醛树脂胶固化及固化动力学研究

采用非等温差示热量扫描DSC曲线方法探讨了竹材液化物酚醛树脂胶不同物质的量之比时的固化反应过程。在25～300℃温度范围内,运用Kissinger方程对不同的升温速率下竹材液化物酚醛树脂胶的DSC曲线进行了固化动力学研究。结果表明:随着甲醛配比的提高(苯酚与甲醛物质的量之比分别为1:1.3、1:1.6、1:1.8),竹材液化物酚醛胶的固化过程表观活化能逐渐减小,分别为64.60、58.36、57.12 kJ/mol;3种配比的竹材液化物酚醛胶的固化反应模型分别为:da/dt=1.30×10⁵e^-64600/RT(1-a)^0.9054,da/dt=1.37×10⁵e^-58360/RT(1-a)^0.8971和da/dt=1.44×10⁵e^-57120/RT(1-a)^0.8959;随着甲醛配比的提高,利用外推法得出的静态(β=0 K/min)的特征固化温度T_i、T_p和T_f均逐渐降低,结果与竹材液化物酚醛胶固化反应的表观活化能的大小顺序一致。

Study on the Curing Characteristics and Kinetics of Bamboo Liquefaction Phenolic Resin

The curing reaction process of bamboo liquefaction phenolic resin with different molar ratio was studied by non-isothermal differential scanning calorimetry (DSC). The Kissinger equation was used to study curing kinetics of bamboo liquefaction phenolic resin based on the DSC curves at different heating rates in the temperature range of 25～300 ℃. The results showed that: with the increase of formaldehyde molar ratio of phenol to formaldehyde (1:1.3,1:1.6,1:1.8), the apparent activation energy was 64.60,58.36 and 57.12 kJ/mol, respectively, which gradually decreased during the curing process of bamboo liquefaction phenolic resin. The curing reaction model of bamboo liquefaction phenolic resin in three different types of molar ratio is da/dt=1.30×10⁵e^-64600/RT(1-a)^0.9054, da/dt=1.37×10⁵e^-58360/RT(1-a)^0.8971 and da/dt=1.44×10⁵e^-57120/RT(1-a)^0.8959, respectively; with the increase of formaldehyde molar ratio of phenol to formaldehyde, the static (β=0℃/min)characteristics curing temperature T_i,T_p and T_f from extrapolation all decreased. The research result agree with the value order of the bamboo liquefaction phenolic resin curing reaction apparent activation energy.