| Summary: | 碩士 === 中國文化大學 === 材料科學與奈米科技研究所 === 98 === This thesis consists of two different parts to investigate mPE based compatibilizer on the effect of different composite systems.
The first part is the preparation of mPE8003/mPE8100-g-silane/clay. Metallocene polyethylene-octene elastomer (mPE8003)/clay nanocomposites were prepared and investigated by using a mPE8100-g-silane as a compatibilizer. Metallocene polyethylene(mPE8100) was grafted with vinyl triethoxy silane at first, and then followed by the mixing with mPE8003 and clay. The crosslinking reaction was conducted in water at 70℃. Two different clays, chemically modified clay Closite 20A and Closite 30B, have been used in this study.
The result of FT-IR revealed silane was essentially grafted on mPE8100. The gel content measurement revealed the compatibilizer efficiently reacted with clay 20A, but not for clay 30B system. From the result of XRD analysis, mPE8003/mPE8100-g-silane/clay 20A showed a better dispersion than mPE8003/mPE8100-g-silane/clay 30B. Transmission Electron Microscope (TEM) revealed a similar result with XRD analysis. In the mPE8003/mPE8100-g-silane/clay 20A system, the clay was dispersed within the polymer matrix in delaminated threads shape, but was observed as lumps for clay 30B system. DSC results revealed the melting temperature was not obviously changed with the amount of clay. But the crystallization temperature of mPE8003/mPE8100-g-silane/clay 20A is higher than that of mPE8003/mPE8100-g-silane/clay 30B. From the result of TGA analysis, the decomposition temperature was obviously increased with increasing the amount of clay, and clay 20A system is much higher than clay 30B system. DMA analysis showed the storage modulus at the room temperature was increased with increasing the clay contents. From the tensile test, Young’s modulus was increased with increasing clay 20A content, but for clay 30B cases. This was attributed to the high surface area between the polymer and the clay 20A. The result of tear test revealed the tear strength was obviously increased with increasing the amount of clay for both clay 20A and clay 30B systems.
The second part is the study on PA6(Polyamide 6)/mPE-g-MA(Maleic anhydride) binary composites. mPE and mPE-g-MA were pre-mixed with 10 phr NIR(Near infrared reflective pigment), manufactured by Tokan Material Technology, at 165 ℃ to form NmPE and NmPE-g-MA master batches, respectively. Then, variable amounts of NmPE and NmPE-g-MA were mixed with PA6 100 phr at 230 ℃ to prepare PA6/NmPE and PA6/NmPE-g-MA composites, respectively, which were investigated on their micro-structure, thermo properties and mechanical properties.
The result of FT-IR (Fourier transform spectroscopy) revealed MA was essentially grafted on mPE. FE-SEM(Field emission scanning electron microscope) photos showed the compatibility of PA6/NmPE-g-MA(samples were all essentially etched by p-xylene) is better than PA6/NmPE. From XRD(X-ray diffraction) analysis, results of two series samples, α-crystal peaks appeared at 20° and 24°, and γ-crystal rarely appeared at 22°. The results of TGA(Thermo gravimetric analyzer) showed limited difference between PA6/NmPE and PA6/NmPE-g-MA at 5 %and 50 % weight loss, and ash content varied with NIR proportion. DSC results revealed that both PA6/NmPE and PA6/NmPE-g-MA composites all showed three melting temperatures(Tm), including Tm of mPE, α-crystal and γ-crystal for PA6. The Tm peak of α-crystal is bigger than γ-crystal, this result was confirmed by XRD. From tensile test, elongation of two systems were increased with elastomer content, but Young’ s modulus showed an opposite trend to elongation. On comparing of two systems, Elongation and Young’ s modulus were higher for PA6/NmPE-g-MA than PA6/NmPE. From impact test, the impact strength was increased with increasing elastomer content for both systems. And, impact strength of PA6/NmPE-g-MA is higher than PA6/NmPE.
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