Polymer composites reinforced with natural fibers have received widespread attention due to the harmful effects of the petroleum derived synthetic polymer waste. In this study, wheat bran (WB), as a new source of natural fiber, has been investigated in manufacturing bio-based composites. Wheat bran was pretreated with sodium hydroxide (NaOH) and the compositions were analyzed. Pretreatment removed fat, starch, and crude protein significantly and resulted in an increase of cellulose content from 10.9% to 29.6%. Polypropylene (PP) was melt-blended with bran in a screw-extruder with and without using a chemical compatibilizer, and test specimens were produced by an injection molder. Composite specimens tested for characterization of different thermophysical properties. A 16.3 % increase in flexural strength was obtained at fiber loading of 20 % or more, while tensile strength was comparable to neat PP using compatibilizer. Moduli increased and impact strength decreased with fiber addition. The highest tensile and flexural moduli were 2838 and 1702 MPa, respectively for WB/PP composite. The highest impact strength reduction was 66 % with WB/PP composite at 30 % loading rate. Thermal expansion coefficient of the WB/PP biocomposites decreased with a highest reduction of 64 %; meaning that WB, a grain by-product, is very promising as functional fibers for polymer materials. The interactions of WB fiber in bio-based polymer matrix for failure mechanism and composite strength were also studied by manufacturing WB/polylactic acid (PLA) composites using fiber loading optimized for WB/PP composite. Inferior mechanical performance of WB/PLA composites was observed compared to neat PLA. Poor adhesion, debonding, and fiber fracture were the dominating micromechanical deformation processes in WB/PP composites, whereas debonding, cavity, and crack formation due to fiber orientation resulted in poor performance of WB/PLA composites. Prospects of WB-based composites present opportunities for growers having beneficial uses of bran and compensating reduced profit margins.

由于石油衍生的合成聚合物废料的有害影响，用天然纤维增强的聚合物复合材料受到了广泛关注。在这项研究中，麦麸 (WB) 作为一种新的天然纤维来源，已被研究用于制造生物基复合材料。用氢氧化钠 (NaOH) 预处理麦麸并分析其组成。预处理显着去除了脂肪、淀粉和粗蛋白，使纤维素含量从 10.9% 增加到 29.6%。聚丙烯 (PP) 与麸在螺杆挤出机中使用和不使用化学增容剂进行熔融共混，并通过注塑机生产测试样品。测试复合样品以表征不同的热物理特性。一个 16。在纤维填充量为 20% 或更多时，弯曲强度增加了 3%，而拉伸强度与使用增容剂的纯 PP 相当。随着纤维的加入，模量增加而冲击强度降低。WB/PP 复合材料的最高拉伸和弯曲模量分别为 2838 和 1702 MPa。WB/PP 复合材料在 30% 的加载率下，最高的冲击强度降低了 66%。WB/PP 生物复合材料的热膨胀系数下降，最大下降 64%；这意味着 WB 作为一种谷物副产品，作为聚合物材料的功能纤维非常有前途。通过使用为 WB/PP 复合材料优化的纤维负载制造 WB/聚乳酸 (PLA) 复合材料，还研究了 WB 纤维在生物基聚合物基质中对失效机制和复合材料强度的相互作用。与纯 PLA 相比，观察到 WB/PLA 复合材料的机械性能较差。WB/PP 复合材料的微机械变形过程主要是粘附性差、脱粘和纤维断裂，而纤维取向导致的脱粘、空腔和裂纹形成导致 WB/PLA 复合材料的性能不佳。基于 WB 的复合材料的前景为种植者提供了机会，他们可以有益地利用麸皮并弥补利润率的下降。