...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Polymers for advanced technologies >Preparation and characterization of a polyimide nanofoam through grafting of labile poly(propylene glycol) oligomer
【24h】

Preparation and characterization of a polyimide nanofoam through grafting of labile poly(propylene glycol) oligomer

机译：通过不稳定的聚丙二醇低聚物的接枝制备聚酰亚胺纳米泡沫并进行表征

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Preparation of a polyimide nanofoam (PI-F) for microelectronic applications was carried out using a polyimide precursor synthesized from poly[(amic acid)-co-(amic ester)] and grafted with a labile poly(propylene glycol) (PPG) oligomer. Polyimide precursor was synthesized by partial esterifica-tion of poly(amic acid) (PAA) derived from pyromellitic dianhydride (PMDA) and 4,4/-oxydianiline (ODA). The precursor was then grafted with bromide-terminated poly(propylene glycol) in the presence of K{sub}2CO{sub}3 in hexamethylphosphoramide and N-methylpyrrolidone, imidized at 200℃ in nitrogen and the product was subsequently decomposed in air at 300℃ to eliminate the labile PPG oligomer to produce PMDA/ODA polyimide nanofoam. Nuclear magnetic resonance spectro-scopy (H-NMR) and Fourier transform infrared spectroscopy (FT-IR) techniques were used to characterize the formation of polyimide precursor and extent of grafting of PPG with polyimide. The results of thermogravimetric analysis (TGA) showed three step decomposition of nanofoam with the removal of PPG at 350℃ and decomposition of polyimide at around 600℃ The polyimide nanofoams were also characterized by small angle X-ray scattering (SAXS), field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The morphology showed nanophase-separated structures with uniformly distributed and non-interconnected pores of 20-40 nm in size. Dynamic mechanical analysis (DMA) indicated higher storage modulus for the foamed structure compared to the pure PI with reduction in loss tangent for the former system.
机译：使用由聚[（酰胺酸）-共-（酰胺酸酯）]合成并接枝了不稳定的聚丙二醇（PPG）低聚物的聚酰亚胺前体，制备了用于微电子应用的聚酰亚胺纳米泡沫（PI-F） 。聚酰亚胺前体通过衍生自均苯四甲酸二酐（PMDA）和4,4 /-二氧二苯胺（ODA）的聚酰胺酸（PAA）的部分酯化反应合成。然后在六甲基磷酰胺和N-甲基吡咯烷酮中，在K {sub} 2CO {sub} 3存在下，将溴化物封端的聚丙二醇接枝前体，在氮气中于200℃酰亚胺化，随后将产物在空气中于300℃分解。 ℃消除不稳定的PPG低聚物，生产PMDA / ODA聚酰亚胺纳米泡沫。核磁共振波谱（H-NMR）和傅立叶变换红外光谱（FT-IR）技术用于表征聚酰亚胺前体的形成以及PPG与聚酰亚胺的接枝程度。热重分析（TGA）结果表明，在350℃下PPG去除后，PPG去除了纳米泡沫的三步分解;在600℃左右时，聚酰亚胺分解了。扫描电子显微镜（FE-SEM）和透射电子显微镜（TEM）。形态显示出纳米相分离的结构，具有均匀分布且大小为20-40 nm的非互连孔。动态力学分析（DMA）表明，与纯PI相比，泡沫结构的储能模量更高，前者的损耗角正切降低。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号