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SYNPOSISAn interfacial model was proposed for the ternary thermoplastics (matrix)/elastomer/rigidparticle filler composite with high strength, high toughness, and high modulus. A dispersed phase of rigid particle as a core and elastomer as a shell that has a good interfacial adhesion with the matrix is the key point of the model. A composite with high strength, high toughness, and high modulus was obtained in the styrene (ST) and maleic anhydride (MAH) modified high-density polyethylene (HDPE)/ethylene-propylene-diene monomer (EPDM) rubber/ carbon black (CB) with ditertiary butyl peroxide (DTBP) as the initiator through the reactive extrusion. The electrical resistivity measurement showed that CB of the unmodified composites distributed at the interface of the HDPE and EPDM, while that of the modified composites distributed mainly in the EPDM phase. The morphology of the ternary composite was consistent with the wetting coefficient analysis. That the mechanical properties of the y-ray-irradiated unmodified composites were not as good as those of the modified composites further indicated that the mechanical properties of the composite could not be improved significantly purely by introducing the interfacial adhesion and matrix crosslinking without forming the proposed dispersed phase structure. SEM observation supported the conclusion that the different phase structures are the major reason that leads to the different toughness. INTRODUCTIONRecently, rigid-particle fillers have been extensively used in creating a polymer composite with high strength, high modulus, and low shrinkage.',' However, the decreased toughness generally results for the c o m p o~i t e .~ On the other hand, elastomers are generally employed in increasing the polymer toughness, but generally result in the deteriorated In a word, two-phase composites exhibit only a partial improvement over the matrix material alone, because some selected properties are enhanced a t the expense of others.* To whom correspondence should be addressed.Journal of Applied Polymer Science, Vol. 59, 287-294 (1996) 0 1996 John Wiley & Sons, Inc.CCC 0021-8995/96/020287-08 In our earlier work, a kaolin-toughened polypropylene l1 and polyamide 6 l2 composite was obtained. In the case of kaolin-toughened polypropylene, an elastic interlayer that had a good interfacial adhesion with the kaolin was inserted between the filler and matrix; therefore, the toughness of the composite was increased significantly. But due to the lack of interfacial adhesion between the interlayer and the matrix, the strength of the composite was not improved. In the case of the kaolin-toughened polyamide 6, the interfacial adhesion both between the filler and interlayer and between the interlayer and matrix was good due to the presence of functional group in both the filler and the matrix. A polyamide 6 composite with high strength, high toughness, and high modulus was obtained. The functionalization of the matrix was not present in the nonpolar polypropylene. As a result, the above interfac...

Investigation of the effects of an interfacial modifier on the rheological behavior of binary high‐density polyethylene (HDPE) composites showed that the interfacial modifier significantly changed the melt state behavior of HDPE/carbon black (CB) composites. This suggests that the interfacial adhesion between the CB surface and the HDPE is significantly improved by the incorporation of the interfacial modifier. Although the dispersion of filler in the matrix was improved, HDPE was also temporarily crosslinked by the CB Particles in the melt due to the strong interfacial interaction. For HDPE/ethylene propylene diene rubber (EPDM) composites, incorporation of CB caused limited change of the melt state behavior. Addition of interfacial modifier to the HDPE/EPDM/CB composite also resulted in a change of the melt state behavior compared with the unmodified composite, but the effect was not so pronouced as that in the HDPE/CB composites. The difference is well explained by the different phase structure. A core–shell dispersed phase structure with the filler as a core and rubber as a shell was formed in the modified composite, with the crosslinking effect predominating in the dispersed phase, while a separate filler and rubber dispersed phase predominated in the unmodified composite. The conclusion is further supported by the solid state dynamic mechanical analysis in a previous paper and SEM micrographs in this paper.

Permanent magnet speed regulation is an energy-saving technology that uses magnetism coupling to realize the torque transmission of non-mechanical connection and changes the gap of the permanent magnetic coupler to adjust the speed of the load. Experimental research on the air-cooled permanent magnet speed regulation according to the actual operation parameters of 500 kw oxidation fan has been conducted in this paper. Analyses of the problems about the rupture of the load ring at the end of the load on the permanent magnetic speed regulation, large motor vibration, noise and so on appeared during the process of the test have been made and improved measures are proposed.

=Quasi-one-dimensional periodic systems were investigated by the new proposed extrapolation method. The effect of the selection of the different structural units and their spin states on the periodic system was also studied. A quantum chemical calculation investigation of a 28 quasi-one-dimensional periodic system with MNDO (UHF) and EHMO/ASED-EHCO/ASED was undertaken. Quantum chemical calculation results with the MNW (UHF) method showed that the proposed new method could be applied in the situation of the more precise semiempirical method. The selection of the different structural units and their spin states do not affect the extrapolated structural unit energy. The energy of suspending terminal group is generally higher for those with a higher bond order. The interaction energy between the suspending terminal groups generally decreases with the chain length. Comparison between the extrapolation results of EHMO/ASED and those from the crystal orbital calculation of EHCO/ASED indicates their equivalence, thus confirming the validity of the proposed method. witnessed a growing interest directly related to the many appealing properties displayed by them. Polymers and molecular crystals are all periodic systems composed of repeated structural units, and then, in principle, their properties can be determined by the structural units. However, generally, the traditional method LCAO/MO-LCMO/CO