热压时间和温度对酚醛树脂型超薄高密度纤维板性能的影响

Effects of Hot-Pressing Time and Temperature on Properties of Phenolic Resin Ultra-Thin High Density Fiberboards

超薄高密度纤维板作为纤维板行业的新兴产品,因其超薄的厚度(<1.5 mm)在胶合板贴面、建筑装饰装修等饰面领域广泛应用。以酚醛树脂(PF)为胶黏剂,探讨热压时间(60、90和120 s)和热压温度(150、170和190℃)变化对1 mm厚PF超薄高密度纤维板的弯曲强度、内结合强度和24 h吸水厚度膨胀率的影响,并使用扫描电子显微镜观察纤维和树脂结合状况。研究结果表明,在一定范围内随着热压时间的延长和热压温度的升高,纤维板的性能逐渐提高;当热压时间为120 s,热压温度为190℃时,纤维板的性能最优,其弯曲强度达到88.5 MPa,内结合强度达到5.70 MPa,24 h吸水厚度膨胀率为6.8%,达到团体标准T/CNFPIA 3007—2019《超薄高密度纤维板》的要求。

As a new product in the fiberboard industry,ultra-thin high density fiberboards have been widely used as veneers for the plywood furnishing,architectural decoration,and other fields because of the ultra-thin thickness(about 1.5 mm).In this study,phenol-formaldehyde resin(PF)was used as an adhesive to investigate the effects of the hot-pressing time(60,90,and 120 s)and temperature(150,170,and 190℃)on the modulus of rupture,internal bonding strength,and the 24 h water absorption thickness swelling rate(24 h TS)of 1 mm PF ultra-thin fiberboards.The scanning electron microscope was used to observe the bonding situation between fiber and resin.The results showed that with the extension of the hot-pressing time and the increase of hot-pressing temperature within a certain range,the performance of fiberboards was gradually improved.When the hot-pressing time was 120 s and the hot-pressing temperature was 190℃,the performance of fiberboards was the best.The modulus of rupture reached 88.5 MPa.The internal bonding strength reached 5.70 MPa and the 24 h TS was 6.8%.These properties meet the requirements of the standard T/CNFPIA 3007—2019 Ultra-Thin High Density Fiberboard.