Adaptation of Multi Walled Carbon Nanotubes on Viscoelastic and Damping Behavior of Flax Fiber Composite

ABSTRACT

Damping characteristics and viscoelastic behavior of flax/epoxy composites reinforced with carboxyl-functionalized multi-walled carbon nanotubes (COOH-MWCNT) were investigated in this study. The viscoelastic behavior was studied utilizing dynamic mechanical analysis (DMA), conducted on all the fabricated composite specimens and neat-resin (pure epoxy). The results revealed an improvement in glass transition temperature (T_g) for flax epoxy composites with 0 wt.%, 0.5 wt.%, and 1 wt.% reinforcement of MWCNT when compared to the free-resin. From the obtained graphs, C-factor was estimated, adhesion factor and Cole–Cole plots were drawn. The frequency response function (FRF) plot, obtained from free vibration testing, unveils the natural frequencies at mode-I and mode-II vibration, and their respective damping ratios are estimated by half-power bandwidth method. The damping ratios and the natural frequencies increased with the addition of MWCNT. The flax/epoxy composite reinforced with 1 wt.% of MWCNT was found to prevail over the rest by exposing great vibration damping, viscoelastic and mechanical properties.

摘要

研究了羧基官能化多壁碳纳米管 (COOH-MWCNT) 增强亚麻/环氧复合材料的阻尼特性和粘弹性行为. 利用动态力学分析 (DMA) 对所有制造的复合材料试样和纯树脂 (纯环氧树脂) 进行粘弹性行为研究. 结果表明, 与游离树脂相比, 添加0 wt.%, 0.5 wt.%和1 wt.%MWCNT的亚麻-环氧复合材料的玻璃化转变温度 (T_g) 有所提高. 根据获得的曲线图, 估算了C因子, 绘制了粘附因子和油菜-油菜曲线图. 从自由振动测试中获得的频率响应函数 (FRF) 图揭示了I型和II型振动的固有频率, 并通过半功率带宽法估计了它们各自的阻尼比. 随着MWCNT的加入, 阻尼比和固有频率增加. 发现1%MWCNT增强的亚麻/环氧复合材料具有良好的减振, 粘弹性和力学性能, 优于其他材料.

KEYWORDS:

• Flax fiber
• multi-walled carbon Nano-Tube
• free vibration test
• dynamic mechanical analysis
• mechanical properties
• Cole–Cole plot

关键词:

• 亚麻纤维
• 多壁碳纳米管
• 自由振动试验
• 动态力学分析
• 力学性能
• 科尔-科尔曲线图

Disclosure statement

No potential conflict of interest was reported by the author(s).

Research highlights

• Influence of nano-additives in the resin aiming to achieve the improved mechanical properties and other primary characteristics has been gaining the demand among the researchers today.

• Emphasizing the natural fiber advantages with identified inherent strength properties leads to replace the polymers in use.

• Sound absorbing properties and vibration damping properties are often secondary design criteria in composite structures, whereas mechanical performance and weight are primary concerns.

• The flax/epoxy composite reinforced with 1 wt.% of MWCNT was found to prevail over the rest by exposing great vibration damping.

• Chain mobility was reduced as a result of the enhanced bonding between matrix and fiber generated by the inclusion of MWCNT, lowering the loss modulus.