PDF(Pubmed)
Abstract：
The canola oil industry generates significant waste as canola meal (CM) which has limited scope and applications. This study demonstrates the possibility of valorization of CM as a sustainable natural filler in a biodegradable polymer composite of Poly(lactic acid) (PLA). Generally, interfacial bonding between natural fibers and the polymer matrix in the composite is weak and non-uniform. One possible solution is to derivatize natural fibre to introduce interfacial bond strength and compatibility with the PLA polymer matrix. Here, CM was succinylated in a reactive extrusion process using succinic anhydride at 30 wt% to get 14% derivatization with 0.02 g of -COOH density per g of CM. The CM or succinylated CM at 5 and 15 wt% was co-extruded with amorphous PLA to get composite fibers. CM-PLA and succinylated CM-PLA biocomposites were foamed using a mild and green microcellular foaming process, with CO2 as an impregnating agent without any addition of organic solvents. The properties of the foams were analyzed using differential scanning calorimetry (DSC), Dynamic mechanical thermal analysis (DMTA), shrinkage, and imaging. The addition of CM or succinylated CM as a natural filler did not significantly change the glass transition temperature, melting point, percent crystallization, stiffness, and thermal stability of PLA foams. This suggests succinylation (modification) of CM is not a mandatory step for improving interphase compatibility with the amorphous PLA. The new PLA-CM foams can be a good alternative in the packaging industry replacing the existing petroleum-based polymer foams.
摘要：
低芥酸菜籽油工业产生大量废物作为低芥酸菜籽粉(CM),其具有有限的范围和应用。这项研究表明，在可生物降解的聚乳酸（PLA）聚合物复合材料中，CM作为可持续的天然填料的价值化的可能性。一般来说,复合材料中天然纤维与聚合物基体之间的界面结合较弱且不均匀。一种可能的解决方案是衍生天然纤维以引入界面结合强度和与PLA聚合物基质的相容性。这里,在反应性挤出过程中使用琥珀酸酐以30wt%将CM琥珀酰化以获得14%的衍生化,其中0.02g-COOH密度/g的CM。将5和15重量%的CM或琥珀酰化CM与无定形PLA共挤出以获得复合纤维。CM-PLA和琥珀酰化CM-PLA生物复合材料发泡使用温和和绿色微孔发泡工艺，用CO2作为浸渍剂，不添加任何有机溶剂。使用差示扫描量热法（DSC）分析泡沫的性能，动态机械热分析(DMTA)收缩，和成像。添加CM或琥珀酰化CM作为天然填料并没有显着改变玻璃化转变温度，熔点,结晶百分比，刚度,聚乳酸泡沫的热稳定性。这表明CM的琥珀酰化(改性)不是用于改善与无定形PLA的相间相容性的强制性步骤。新的PLA-CM泡沫可以替代现有的基于石油的聚合物泡沫在包装工业中是良好的替代品。
