基于膨润土的脲醛树脂填料的开发与性能研究

Study on exploiture and performance of bentonite as filler of urea-formaldehyde resin

比较了面粉、膨润土及其用量对脲醛(UF)树脂胶粘剂的pH值、固含量、固化时间和胶合强度的影响,探讨了膨润土用作胶粘剂填料的可行性。研究结果表明:随着膨润土用量的增加,UF树脂胶粘剂的pH值、固化时间和固含量呈递增趋势,游离甲醛含量明显下降;随着面粉用量的增加,UF树脂胶粘剂的固含量和固化时间呈递增趋势(但增幅比膨润土体系小),pH值有所降低;用添加膨润土的UF树脂胶粘剂生产的胶合板,当w(膨润土)≤20%、施胶量为280～300 g/m2时,胶合板的湿态胶合强度(1.69 MPa)比面粉体系(1.53 MPa)和纯UF树脂胶粘剂体系(1.09 MPa)的高,其湿态胶合强度能达到GB 9 846-1988的标准,而干态胶合强度则远高于GB 9 846-1988标准。

The influences of flour, type and content of bentonite on the pH value, solid content, curing time and bonding strength of urea-formaldehyde （U F ） resin adhesive were studied. The feasibility was discussed with ben- tonite as adhesive filler. The research results showed that with the increase of bentonite filler content, the pH value, curing time and solid content for UF resin adhesive have trend of increase by degrees, but free formaldehyde content was decrease obviously. With the increase of flour content, the curing time and solid content for UF resin adhesive have trend of increase by degrees （growth was less than bentonite system）, but pH value was decrease little. When mass fraction of bentonite was no above 20% and the adhesive content was between 280 g/m2 and 300 g/m2, the wet bonding strength （1.69 MPa） of plywood which was produced by UF resin adhesive with bentonite as filler was more than by UF resin adhesive with flour as filler （ 1.53 MPa） and by pure UF resin adhesive （ 1.09 MPa）, the dry bonding strength was more than GB 9 846-1988 standard and the wet bonding strength met request of GB 9 846-1988 standard.