This work provides a study about the incorporation of a high density polyethylene (HDPE) matrix composite in medium density fiberboards (MDF). A composite was processed in a single screw extruder with 5% of Pinus spp fibers in a HDPE matrix and applied as reinforcing agent in MDFs, as well as pure HDPE, in 11 different variations, using 12% of urea-formaldehyde resin and nominal density of 750 kg.m−3. The composite and the pure HDPE were analyzed by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The DSC results showed that both polymeric matrix and composite presented the same melting temperature but the composite had a reduced melting enthalpy and crystallinity due to thermal history. SEM analysis showed a well distribution of fibers on the composite. The results of technological properties of MDFs were compared to commercial MDF standards. The MDF reinforced with 40% of polymeric composite reached all minimum standard requirements, being the most recommended to be used as an alternative to conventional MDF, in terms of physical and mechanical performance.

中文翻译：

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高密度聚乙烯基复合材料作为中密度纤维板的增强剂

这项工作提供了一项关于在中密度纤维板 (MDF) 中加入高密度聚乙烯 (HDPE) 基复合材料的研究。一种复合材料在单螺杆挤出机中加工，在 HDPE 基质中含有 5% 的松属植物纤维，并用作中密度纤维板和纯 HDPE 的增强剂，有 11 种不同的变化，使用 12% 的脲醛树脂和标称密度750 kg.m−3。通过差示扫描量热法 (DSC)、热重分析 (TGA) 和扫描电子显微镜 (SEM) 分析复合材料和纯 HDPE。DSC 结果表明聚合物基体和复合材料具有相同的熔化温度，但由于热历程，复合材料的熔化焓和结晶度降低。SEM 分析表明复合材料上的纤维分布良好。将 MDF 的技术性能结果与商业 MDF 标准进行了比较。用40%的聚合物复合材料增强的MDF达到了所有最低标准要求，在物理和机械性能方面是最推荐用作传统MDF的替代品。