Dependence of the Dynamic Mechanical Properties and Structure of Polyurethane-Clay Nanocomposites on the Weight Fraction of Clay
Dependence of the Dynamic Mechanical Properties and Structure of Polyurethane-Clay Nanocomposites on the Weight Fraction of Clay
复制标题
DOI：
10.3390/jcs6060173
复制
发表时间：
2022-06-01
影响因子：
3.3
通讯作者：
Iroh, Jude O.
中科院分区：
文献类型：
--
作者：
Peng, Shirley;Iroh, Jude O.
研究了粘土和化学交联对不同浓度有机改性蒙脱土增强聚氨酯动态力学性能的影响。聚氨酯基体由聚四氢呋喃软段和4，4 '-亚甲基双（苯基异氰酸酯）硬段组成。甘油被用作化学交联剂，而Clopartan 30 B粘土是增强填料。所述纳米复合材料含有至多1重量%的粘土显示出粘土的均匀分散;然而，含有较高浓度粘土的纳米复合材料显示出不均匀性的存在。动态力学光谱，DMS揭示了含有2和10重量%之间的纳米复合材料，粘土具有两个玻璃化转变温度，T-g，T-1和T-g，T-2。高温玻璃化转变温度T-g、T-2随粘土含量的增加而增加，低温玻璃化转变温度T-g、T-1随粘土含量的增加而降低。所述纳米复合材料含有高达1重量%的低粘土浓度，仅显示一个玻璃化转变温度，具有窄的玻璃化转变区域。纳米复合材料的交联密度随着wt.%的增加而增加。克莱
The effect of clay and chemical cross-linking on the dynamic mechanical properties of polyurethane reinforced with different concentrations of organically modified montmorillonite clay is investigated in this study. The polyurethane matrix is constituted of polytetrahydrofuran soft segment and 4,4 '-methylenebis(phenyl isocyanate) hard segment. Glycerin was used as the chemical crosslinking agent, while Cloisite 30B clay was the reinforcing filler. The nanocomposites containing up to 1 wt.% clay showed a uniform dispersion of clay; however, the nanocomposites containing higher concentrations of clay showed the presence of heterogeneities. Dynamic mechanical spectroscopy, DMS revealed that the nanocomposites containing between 2 and 10 wt.% clay had two glass transition temperatures, T-g,T-1 and T-g,T-2. The higher-temperature glass transition temperature, T-g,T-2 increased with increasing clay concentration, while the low-temperature glass transition temperature, T-g,T-1 decreased with increasing clay concentration. The nanocomposites containing low clay concentrations up to 1 wt.% showed only one glass transition temperature with a narrow glass transition region. The crosslink density for the nanocomposites increased with increasing wt.% clay.