1,3-Bis(4-(p-aminophenoxy)phenyl-1,1,3,3-tetramethyldisiloxane (BAPPSi) and 2,2-bis(4- (p-aminophenoxy)phenylpropane (BAPPA) were synthesized by terminal nitrophenyl etherification of 1,3-bis(p-hydroxyphenyl)disiloxane (HPDS) and bisphenol-A, respectively, followed by reduction using hydrogen with Pd-C catalyst. Two types of polyimide were prepared via polyamic acids by using corresponding diamines, BAPPSi and BAPPA, with some aromatic acid dianhydrides. The curing temperature for imidation was determined as 200 °C for 1 hour by FT-IR spectra of temperature conversion in the reaction. This condition was for 1 hour. Properties such as heat resistance (5% weight loss temperature), water contact angle, and adhesion toward glass were compared between these polyimides. Water repellency and adhesion of polyimide-siloxanes after 50 hr at 120 °C and 95%RH were superior to those of usual polyimides without siloxanes, although heat resistance of both polyimides was almost same extent (< 500 °C). The blend-polyimides prepared by mixing corresponding polyamic acids derived from BAPPSi and BAPPA showed higher adhesive ability than copolyimides from copolyamic acids using both diamines. It was found that even small amount of siloxane in the blend-polyimides contribute to enhancing the adhesion toward glass.

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The influences of interfacial structure of polypropylene (PP) filled with alkyl sulfonate treated CaCO3 particles (mean particle size; 0.9 mm) on the mechanical and electrical properties of the composites were investigated. Scanning electron microscopic observation of the cross sections of the composites showed that the treated particles were well dispersed in the matrix. After standing for 10 days, the resistivity of the composites filled with the treated CaCO3 at a content of 40wt% decreased from 10 16 to 10 12 Ω•cm. The modulus of the composite was decreased by the treatment of CaCO3 with alkyl sulfonate. The yield strength of PP filled with non-treated CaCO3 decreased gradually with increasing CaCO3 content. On the other hand, the yield strength of PP filled with alkyl sulfonate-treated CaCO3 decreased gradually with an increase in CaCO3 content up to 40wt%, whereas it was almost constant at the content above 40wt%. The compound of alkyl sulfonate-treated CaCO3 improved the impact strength of PP matrix. The maximum impact strength of 69 kJ • m- 2 was obtained in the 6wt% alkyl sulfonate-treated CaCO3 composite at a CaCO3 content of 40wt%. These results suggested that the region around the particles where alkyl sulfonates were diffused was formed in the PP matrix, and the overlapping of the regions expected to result in the conduction path.

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