使用激素诱导的阴离子正面聚合,自由立体3D打印环氧-乙烯基乙结构
Brecklyn R Groce1, Alexandra V Aucoin1, Md Asmat Ullah2
1Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States.
ACS applied polymer materials
|January 17, 2024
概括
额头聚合使得不支持结构的3D打印速度更快,更节能. 这项研究开发了一种用于激素诱导的阴离子正面聚合物的新型树脂,证明了复杂的独立几何形状的成功打印.
科学领域:
- 聚合物化学 聚合物化学
- 添加剂制造 添加剂制造 添加剂制造
- 材料科学 材料科学 材料科学
背景情况:
- 额头聚合为增材制造提供了能源效率和打印速度的优势.
- 它可以创建独立的结构,而不需要支材料.
研究的目的:
- 开发和优化一种树脂系统,用于3D打印中激素诱导的阴离子正面聚合.
- 调查配方组件对前端速度和打印能力的影响.
- 为了证明打印具有复杂几何形状的独立结构的能力.
主要方法:
- 使用环氧体,乙烯基以太和启动系统 (盐和过氧化物) 制定了一种新型树脂.
- 树脂特性 (反应性,质性,物理性质) 为基于挤压的打印进行了优化.
- 一个经过修改的桌面3D打印机控制了树脂挤出和沉积.
- 通过协调紫外线发射,空气压力和打印速度,可以实现单片丝和螺旋形状的独立打印.
主要成果:
- 优化的树脂通过激素诱导的阴离子机制在正面聚合,使得独立结构印刷成为可能.
- 增加的乙烯基以太和环氧化含量增加了前部速度.
- 碳纳米纤维比磨碳纤维更多地提高了前部速度.
- 含有碳纳米纤维和烟雾化的树脂表现出剪切稀释行为,适用于4%重量级的挤压印刷.
- 横向打印的标本由于空隙和粘附问题而具有较低的屈曲强度.
结论:
- 额头聚合是一种可行的技术,用于高能效,高速度的复杂,无支结构的增材制造.
- 树脂配方,特别是乙烯基乙烯和环氧化的比例,显著影响了前极速度.
- 碳纳米材料,特别是纳米纤维,可以提高印刷速度.
- 仔细控制打印参数对于实现所需的机械性能和成功的自由形式制造至关重要.
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