本論文係以傳統自由基聚合法合成有機高分子溶膠-凝膠前驅物 poly(MMA-co-MSMA ),再導入TEOS 進行溶膠-凝膠反應,將TEOS 水解、縮合後產生二氧化矽無機物網絡,以製備poly(MMA-co -MSMA)/SiO2 混成材料。 本研究中添加之MSMA 作為共聚單體外, 並同時扮演者偶合劑的角色,使合成出poly(MMA-co-MSMA)樹脂, 可與無機二氧化矽形成化學共價鍵結,成為poly(MMA-co -MSMA)/ SiO2 混成材料。 由FTIR-RAS 與Solid state 29Si-NMR 顯示, 已製備出 poly(MMA-co -MSMA)/ SiO2 混成材料,並且無機物二氧化矽與有機 高分子有化學鍵生成。 poly(MMA-co-MSMA)/ SiO2 混成材料,隨 TESO 導入量的增多,應用TGA 與DSC 研究其熱穩定性,顯示可提 高熱分解溫度以及玻璃轉移溫度的消失;由傅氏反射式紅外光譜儀 curve fitting 可瞭解,poly(MMA-co-MSMA)/ SiO2 在金屬鐵片上會形 成Si-O-Fe 的化學鍵,TEOS 強化了poly(MMA-co-MSMA)/ SiO2 對金 屬鐵片的附著性; 應用電化學法進行防腐蝕測試, poly(MMA-co-MSMA)因TEOS 的導入形成的二氧化矽,減緩了鐵金 屬的腐蝕速率。 本研究並應用TEM 與AFM 探討二氧化矽在 poly(MMA-co-MSMA)基材中的內層及表面形態。
In this study, a series of PMMA-silica hybrid materials have been successfully prepared through the conventional free radical polymerization reactions with benzoyl peroxide (BPO) and trimlthoxysilylproplymethacrylate (MSMA) as initiator and coupling agent, respectively. First pf all, sol-gel precursor (i.e., P(MMA-co-MSMA) with specific content of MSMA is synthesized, followed by processing hydrolysis and condensation reactions (i.e., sol-gel approach) of the as-prepared copolymer and tetraethyl orthosilicate (TEOS). The as-prepared hybrid materials are then characterized by FTIR, TEM, AFM and 29Si-MNR. The thermal stability and mechanical strength of hybrid materials are found to be higher than that of neat PMMA based on the DSC, TGA and DMA measurements. The anticorrosion effect of hybrid coating is found to be enhanced as the silica content increases based on a series of electrochemical measurements such as corrosion potential, polarization resistance, corrosion current and impedance spectroscopy. The enhancement of corrosion protection effect of hybrid sol-gel coatings may be due to the increase of adhesion strength and surface hydrophobicity on a basis of Scotch tape test, FTIR-RAS, and contact angle test.