改善食品包装纸浆模塑材料的机械性能研究

Study on Improving the Mechanical Properties of Moulded Fiber Materials for Food Packaging

关键词:  纸浆模塑材料  机械强度  纤维种类  增强助剂  模压参数

Key Words:moulded fiber materials  mechanical strength  fiber types  strength additives  moulding parameters

摘要:为了拓展纸浆模塑餐具的纤维原料来源以及改善纸浆模塑材料的机械性能，本研究较系统地探讨了4种纤维原料的特性、打浆适应性、外添助剂及模压参数对纸浆模塑材料机械性能的影响。结果表明，与100%蔗渣浆相比，添加一定量的漂白化学竹浆、漂白化学针叶木浆、漂白化机阔叶木浆均能提升纸浆模塑材料的机械强度，其中阔叶木浆与蔗渣浆之间存在协同增效作用，相较于100%蔗渣浆，阔叶木浆与蔗渣浆以1∶1复配时使得纸浆模塑材料的抗张指数、耐破指数和挺度分别提高了22.0%、65.8%、12.4%；外添助剂中，改性淀粉的增强效果最好，相较于未添加助剂的蔗渣浆模塑材料，当其添加量为1.5%时，抗张指数、耐破指数、挺度分别提高了15.3%、28.3%、9.8%；纸浆模塑材料热压成型过程中，压力对其机械性能影响最大，实验条件下最佳模压参数为170℃、60 s、0.5 MPa。

Abstract:In order to expand the source of fiber raw materials for moulded pulp products and improve the mechanical properties of moulded fiber materials （MFs）， the effects of the process conditions on the mechanical properties of MFs were systematically studied in this paper， including the properties of cellulose fibers， beatability， additives， and moulding parameters. The results showed that the mechanical properties of MFs made by adding a certain amount of bamboo bleached chemical pulp （BBCP）， softwood bleached kraft pulp （SBKP）， and hardwood bleached chemi-thermo-mechanical pulp （HBCTMP）， respectively， were all improved in comparison to that of MFs with 100% bagasse bleached kraft pulp （BBKP）. Especially， there was a synergistic effect between HBCTMP and BBKP， the combination of HBCTMP and BBKP at 1∶1 could increase the tensile index， burst index and stiffness of MFs by 22.0%， 65.8% and 12.4% compared with 100% BBKP-based MFs， respectively. Among the additives in this paper， modified starch performed the best enhancement effect， compared with 100% BBKP-based MFs without any additives， the tensile index， burst index and stiffness increased by 15.3%， 28.3% and 9.8% when the addition amount of modified starch was 1.5%， respectively. Moreover， the pressure showed significant influence on the mechanical properties of MFs during the hot pressing process， and the optimal moulding parameters under the test conditions were 170℃， 60 s， 0.5 MPa.