新穎含磷梯狀聚倍半矽氧烷化合物環氧樹脂奈米複合材料之合成與性質研究

Synthesis and Properties of Novel Phosphorus-containing Ladder Polysilsesquioxanes Epoxy Nanocomposites

劉芳怡(Fang-Yi Liu)

指導教授 ： 馬振基

國立清華大學/工學院/化學工程學系/碩士(2006年)

摘要

本研究旨在利用含磷之梯狀聚倍半矽氧烷(2-(Diphenyl phosphino)ethyltriethoxysilane, DPPETES)及其單體分別與改質及未改質環氧樹脂(DGEBA type epoxy resin)進行反應，並且改變含磷聚倍半矽氧烷之添加比例，製備新穎含磷之梯狀聚倍半矽氧烷環氧樹脂奈米複合材料，由於聚倍半矽氧烷的結構存在下，預期能提升環氧樹脂之熱安定性及難燃性。
本研究以FT-IR、ATR、XRD鑑定奈米複合材料之結構及其反應性；以29Si-NMR鑑定混成複合材料鍵結結構；以DSC、TGA、LOI等測試方式來判定其熱性質，並針對熱反應硬化動力學研究及熱裂解動力學研究兩方面做深入之探討；以SEM、X-ray、Si-mapping、TEM及AFM進行形態學方面研究；並利用透明性及UV/Vis來進行奈米材料之光學性質測試。同時本研究找尋常用硬化劑(mHHPA、D400、DDM)中最適當者及最適當之聚倍半矽氧烷含量。
本研究已成功製備出含100 nm以下且均勻分散之聚倍半矽氧烷化合物環氧樹脂奈米複合材料，最適當之硬化劑為DDM。環氧樹脂系統之矽氧烷鍵結主要為Q3、Q4結構多於T3結構；改質環氧樹脂系統之矽氧烷鍵結主要為T3結構多於Q3、Q4結構。
在反應動力學方面，改質環氧樹脂系統反應活化能高於未改質環氧樹脂系統，反應之最適化DPPETES含量為6 wt%。在熱性質測試中，發現到添加型之未改質環氧樹脂系統其難燃性質優異(LOI 30)，而反應型之改質環氧樹脂系統中，熱穩定性優異(char yield由17.1 %提升至30 %、IPDT 值由589.42提升至955.19)，並能有效降低其熱裂解之速率及提升裂解活化能，裂解活化能也隨DPPETES含量增加而提升。
由整體研究結果可知梯狀聚倍半矽氧烷及其單體最佳之反應濃度為9 wt%，能達到最佳之效能並降低成本。由XRD測試得知分子鏈結構形態為非結晶型高分子化合物，具有透明性質，並由光學性質測試材料在400~800 nm之可見光範圍有接近100 %光穿透特性。未來可能應用於高性能塗料、電子封裝材料、光電材料、建築材料等。

關鍵字

環氧樹脂 ； 聚倍半矽氧烷 ； 溶膠-凝膠 ； 難燃劑

並列摘要

In this study, 2-(Diphenyl phosphino)ethyltriethoxysilane, (DPPETES) was blended with pristine epoxy or modified epoxy (DGEBA) to form a novel ladder-like phosphorus-containing polysilsesquioxane. Furthermore, by changing the blending ratio of phosphorus-containing polysilsesquioxane (PSSQ) to epoxy or modified epoxy, a series of nanocomposites have been prepared. The nanocomposites were predicted to exhibit excellent thermal stability.
FT-IR, ATR, and XRD were used to characterize the reactivity and structure of the nanocomposite in this study. The cured hybrid composite structures of epoxy and modified epoxy with DPPETES and TEOS were investigated by 29Si-NMR. DSC, TGA, and LOI were utilized to analyze the thermal property of the nanocomposite in this study. Moreover, the thermal degradation kinetics and activity energy of curing have been calculated to confirm the high performance thermal properties. Moreover, the optical properties, morphology, physical properties etc. will be discussed. The optimum curing agent and the optimum DPPETES contents were also investigated.
In this study, the polysilsesquioxanes particles were uniform dispersed at the molecular level in epoxy resin and that the sizes of polysilsesquioxanes particles were less than 100 nm. DDM was the optimum curing agent. The silicon atoms with different degrees of condensation were presented in epoxy system and modified epoxy system. The characterizations demonstrated that Q3 and Q4 structures were more dominated than T3 structure in epoxy system. However, the T3 structure was more dominated than Q3 and Q4 structure in modified epoxy system.
From the kinetics analysis of curing reaction, the activation energies of curing of modified epoxy were higher than that in epoxy system and the optimum DPPETES content of curing reaction was 6 wt%. This study also found that either blended or chemical modified nanocomposites show excellent thermal properties.
The nanocomposites of epoxy system (blending) possess excellent flame retardant property (LOI 30). The nanocomposites of modified epoxy (chemical modification) also exhibit excellent thermal stability properties including high char yield (30wt%) , IPDT (955.19), low rate of degradation and high activation energy of degradation. The activation energies of degradation also increased with DPPETES contents. This study reveals that the optimum DPPETES content is 9 wt%.
The XRD patterns show that the chain entanglement resulted in various nanocomponents were amorphous structure, and possessed high optical transparency. The UV/VIS measured for nanocomposites reveal no absorbance in the range of 450~800 nm, it possesses excellent optical transparency. This transmittance may be used as a criterion for identifying the formation of a homogeneous phase.

並列關鍵字

epoxy ； Polysilsesquioxane ； sol-gel ； flame retardance

參考文獻

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