在二氧化纳米管反应器中的综合性聚乙烯纳米纤维:理解超高分子量合成
Kyu Yong Choi1, Joong Jin Han, Bo He
1Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, Maryland 20742, USA. choi@umd.edu
Journal of the American Chemical Society
|February 29, 2008
概括
超高分子量联合性聚乙烯 (sPS) 纳米纤维是使用纳米管反应器 (SNTR) 合成的. 这种方法产生了高度纠的,直径大的聚合物纳米纤维,具有特殊的分子量.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
背景情况:
- 超高分子量聚合物具有独特的机械性能.
- 对聚合物纳米结构的控制合成具有挑战性.
- 合成聚乙烯 (sPS) 是一种半晶体聚合物,在先进材料中具有潜在的应用.
研究的目的:
- 为了合成超高分子量综合性聚烯 (sPS) 纳米纤维.
- 研究在纳米管反应器 (SNTR) 中合成的sPS纳米纤维的形态和结构.
- 为了描述合成的sPS的分子量分布.
主要方法:
- 在SNTR中使用金属催化剂和甲基氨酸共催化剂合成sPS纳米纤维.
- 使用扫描电子显微镜 (SEM) 直接观察纳米纤维挤出.
- 使用传输电子显微镜 (TEM) 将单个SNTR与聚合物纳米纤维分离和观察.
主要成果:
- 在SNTRs中成功合成了超高分子量sPS纳米纤维 (<10nm).
- 观察到薄的sPS纳米纤维聚合成更大的绳状结构 (30-50nm和200nm直径).
- 确定合成的sPS具有超高分子量 (Mw = 928,000 g/mol),其中显著的聚合物在2,000,000-5,000,000 g/mol范围内.
结论:
- 该SNTR是合成超高分子量sPS纳米纤维的有效反应器.
- 合成方法导致复杂,聚合的纳米纤维结构的形成.
- 由此产生的sPS纳米纤维具有异常高的分子量,表明了先进材料应用的潜力.
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