Thipchai Parichat, Jantanasakulwong Kittisak, Sawangrat Choncharoen, Suhr Jonghwan, Khotchapong Kittiphat, Wattanachai Pitiwat, Rachtanapun Pornchai
Nanoscience and Nanotechnology, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand.
Division of Packaging Technology, School of Agro-Industry, Faculty of Agro-Industry, Chiang Mai University, Chiang Mai 50100, Thailand.
Polymers (Basel). 2024 Dec 20;16(24):3558. doi: 10.3390/polym16243558.
This study investigates the microstructural characterization of cellulose nanocrystals (CNC) and microcellulose (MC) extracted from bamboo fibers () and their potential as reinforcement agents in ordinary Portland cement (OPC) composites. CNC with a mean particle size of 29.3 nm and MC with a mean size of 14.6 × 10 nm were incorporated into OPC at varying concentrations (0.1%, 0.2%, 0.4%, and 0.6% by cement mass). The compressive strength analysis revealed that increasing MC content led to a decrease in strength, with reductions ranging from 8.8% to 25.9% relative to the control OPC, while the CNC-enhanced composite at 0.4% achieved the highest compressive strength of 43.2 MPa. Flexural strength analysis indicated a minor increase in strength with MC addition (from 7.5 MPa to 8.1 MPa), while CNC addition at 0.1% improved flexural strength to 8.2 MPa but declined with higher concentrations. SEM and stereo microscopy demonstrated MC and CNC dispersion and highlighted microstructural differences, including pore distribution in the composites. XRD analysis showed increased crystallinity for CNC composites compared to pure OPC, with the highest crystallinity index of 52.2% observed at 0.4% CNC. This study highlights that CNC at specific concentrations can enhance OPC mechanical properties, while higher MC and CNC additions may impact strength properties variably due to their microstructural integration and crystallinity. These findings support the potential for bamboo-derived cellulose materials in enhancing cementitious composite performance.
本研究调查了从竹纤维中提取的纤维素纳米晶体（CNC）和微纤维素（MC）的微观结构特征，以及它们作为普通硅酸盐水泥（OPC）复合材料增强剂的潜力。将平均粒径为29.3 nm的CNC和平均尺寸为14.6×10 nm的MC以不同浓度（按水泥质量计为0.1%、0.2%、0.4%和0.6%）掺入OPC中。抗压强度分析表明，增加MC含量会导致强度降低，相对于对照OPC，强度降低幅度为8.8%至25.9%，而0.4%的CNC增强复合材料达到了最高抗压强度43.2 MPa。抗弯强度分析表明，添加MC会使强度略有增加（从7.5 MPa增加到8.1 MPa），而添加0.1%的CNC可将抗弯强度提高到8.2 MPa，但随着浓度升高而下降。扫描电子显微镜（SEM）和立体显微镜显示了MC和CNC的分散情况，并突出了微观结构差异，包括复合材料中的孔隙分布。X射线衍射（XRD）分析表明，与纯OPC相比，CNC复合材料的结晶度增加，在0.4%的CNC含量下观察到最高结晶度指数为52.2%。本研究强调，特定浓度的CNC可以增强OPC的力学性能，而较高的MC和CNC添加量可能因其微观结构整合和结晶度而对强度性能产生不同影响。这些发现支持了竹源纤维素材料在增强水泥基复合材料性能方面的潜力。
