本研究以不同比例的進料bis-phenol A diglycidyl methacrylate（BisGMA）及2-hydroxyethyl methacrylate（HEMA），使用2,2-Diethoxy-1-phenylethanone (DEAP)為光起始劑，添加不同含量的silica，並以紫外光聚合固化，討論不同BisGMA/HEMA進料比及silica添加量對反應轉化率，交聯網路結構與性質的影響。
　　藉由13C液態及固態核磁共振儀得知，高分子中BisGMA的含量隨著BisGMA進料量增加而上升。由FTIR發現雙鍵轉化率隨BisGMA含量增加而上升。壓縮模數隨BisGMA進料量增加而上升，交聯密度會增加，且網路中物理纏結的密度（Ns）和網路中化學交聯的密度（Nc）都會增加，表示BisGMA的添加同時有助於物理性及化學性的交聯。此外，利用交聯密度與高分子吸水率可計算得出水和高分子間交互作用參數（χ），χ值越大，平衡含水率越低。固化體積收縮率隨BisGMA的進料量增加而下降，因BisGMA比HEMA帶有較多苯環上的不飽和鍵。由TGA實驗發現熱裂解溫度隨BisGMA含量增加而提高，因高分子單體單位中BisGMA的分子結構帶有兩個苯環，與HEMA相比耐熱溫度較高。由動態機械分析發現儲存模數與玻璃轉移溫度(Tg)皆隨BisGMA進料量增加而上升，且玻璃轉移溫度(Tg)隨轉化率增加而上升。接觸角隨BisGMA進料量增加而上升，因BisGMA較HEMA相對疏水。黏著強度隨BisGMA的進料量增加而上升，且樹脂的破壞模式為內聚破壞(cohesive failure)。材料Vickers硬度隨著BisGMA進料量增加而上升。

　　另一方面添加silica的高分子，轉化率隨添加量增加而下降，且添加量較多時在SEM下發現silica粒子產生聚集。添加量增加，平衡含水率下降及接觸角度上升，因在高分子中添加的silica為疏水型的二氧化矽。除此之外，silica添加量增加，可提升材料的壓縮模數、交聯密度及材料Vickers硬度，且網路中物理纏結的密度（Ns）和網路中化學交聯的密度（Nc）都會增加。而silica含量增加時，固化體積收縮率會降低。在高分子中添加無機物時，因碳化的高分子受二氧化矽影響，而堆積於二氧化矽的表面，使殘餘率提高。另外，在高分子中添加適量的無機物可以提高其儲存模數與玻璃轉移溫度(Tg)。而高分子的黏著強度隨silica添加量增加而降低。
　　實驗結果得知當改變BisGMA/HEMA進料比及silica含量時，會影響高分子的網路結構，進而影響到膨潤交聯產物的交聯密度、力學性質、水與高分子的交互作用，及影響乾交聯產物的動態機械性質及熱性質、黏著強度、硬度等性質。
 

Adhesives were prepared by using bis-phenol A diglycidylmethacrylate（BisGMA）and 2-hydroxyethyl methacrylate（HEMA）of different weight ratios in feed, with 2,2-Diethoxy-1-phenylethanone (DEAP) as the photoinitiator. We add silica in various contents of feed and cure BisGMA and HEMA with UV light and the photoinitiator. We examine the effects of BisGMA/HEMA weight ratios in feed and contents of silica on conversion of reaction, network structure, thermodynamic and mechanical properties.
　　According to 13C Solid-state NMR analysis, the contents of BisGMA in polymers increase with increasing the contents of BisGMA in feed.
According to FTIR analysis, as the contents of BisGMA increase, the conversions of double bonds increase. Compressive modulus and crosslinking density increase with increasing the contents of BisGMA in feed. Both of the density of physical entanglement（Ns）and the density of chemical crosslinking in network（Nc） increase with increasing the contents of BisGMA in feed, showing that adding BisGMA is favorable for physical and chemical crosslinking. In addition, the interaction parameters of water and polymers in adhesives (χ) were calculated by crosslinking densities and equilibrium water contents. As the χ values increase, the equilibrium water contents decrease. Curing volume shrinkages decrease with increasing the contents of BisGMA in feed because of BisGMA with more unsaturated bonds than HEMA. We find pyrolysis temperatures by TGA increase with increasing the relative contents of BisGMA. BisGMA monomer units have higher heat resistance temperature compared with HEMA, due to the molecular structure with two benzene rings in BisGMA. According to DMA analysis, the storage modulus and the glass transition temperature (Tg) are increased with the increase in feed amount of BisGMA, and the glass transition temperature (Tg) are increased with increasing the conversion of double bonds. As the contents of BisGMA increase, the contact angle increase, due to BisGMA being relatively more hydrophobic than HEMA. As the contents of BisGMA increase, the adhesive strength increase. And the failure mode of resins is cohesive failure. As the contents of BisGMA increase, the Vickers hardness increase.
On the other hand, As the contents of silica increase, the conversions(FTIR) of double bonds decrease. And we observed with SEM the aggregation of the silica particles at the excess of silica contents. As the contents of silica increase, increasing contact angle and decreasing equilibrium water contents was found because the silica is hydrophobic relative to momomers. In addition, all of compressive modulus, crosslinking densities, Vickers hardness, the densities of physical entanglement in network, and the densities of chemical crosslinking in network increase with increasing the contents of silica. The polymerization volume shrinkages decrease with increasing the contents of silica. Adding inorganic particles in adhesives can raise storage modulus, glass transition temperature, pyrolysis temperatures, and thermal stability of materials. The char yield increases because the carbonization of the polymer is affected by silica and it accumulates at the silica surface. The adhesive strength decrease with increasing the contents of silica.

Experimental results show that when we vary BisGMA/HEMA ratios in feed and silica contents, that will influence the network structure of polymer, thereby affecting crosslinking density of adhesives, mechanical properties, equilibrium water contents, interactions between water and polymers in swollen resins, as well as affecting dynamic mechanical properties, thermal stability, adhesive strength, and Vickers hardness of dry resins.

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