• Analytical Science and Technology
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• v.24 no.6
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• pp.435-442
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• 2011

Polybrominated diphenyl ethers (PBDEs) are a class of brominated flame retardants (BFRs) which have taken much interest recently due to their potential hazardous effects to human body and ecosystem. Many countries and European community prohibits the usage of certain BFRs in electronics and electronic devices (e.g. RoHS). In this perspectives, Korea Research Institute of Standards and Science (KRISS) has designed and practiced proficiency testing programs based on the ISO/IEC 17043 in order to assist laboratory accreditation activities. The programs for interlaboratory comparisons include congeners of PBDE (PBDE-154, 183, 206, 209) in high impact polystyrene (HIPS). A sample bottle that contains 10 g granular HIPS was distributed to 35 participating laboratories and the test results were calculated by the statistical procedure using z-scores to evaluate performance of each laboratory. The results and the laboratory's performance were discussed.

• Polymer(Korea)
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• v.32 no.3
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• pp.251-255
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• 2008

This study suggested antistatic material which can increase anti-static properties and mechanical strength by mixing polystyrene for conveying electronic stuffs with metal salt and ester compound as a anti-static agent. We studied about mechanical, thermal and electrical characteristics by changing the contents of MAH of poly(styrene-co-maleic anhydride), compatibilizer. As the result of measuring residue space charge of the blends of HIPS(75)/TPU(25)/poly(styrene-co-maleic anhydride)(MAH weight ratio : 25, 32, 43.5 wt%), we could find small residue charge in the blend which MAH(25 wt%) was added and it showed the highest values in tensile strength. Additionally we found out the material to which compatibilizer was added kept better anti-static properties than one to which compatibilizer was not added. In the event we could confirm that the adding of PS-co-MAH enables two polymers were mixed well when HIPS/TPU was blended and anti-static agent made easier dissipative in the blend.

• Tribology and Lubricants
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• v.31 no.3
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• pp.95-101
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• 2015

Carbon nanotubes (CNTs) are widely used in polymer composites as filler materials to enhance various characteristics of the composites because of their remarkable mechanical, electrical, and thermal properties. In this study, we investigate the effects of MWCNTs on the electrical and wear characteristics of high-impact polystyrene (HIPS) composites, and compare the results with the effects of carbon black (CB). The HIPS composites are classified as Bare-HIPS, MWCNT-HIPS composites containing 2, 3, 4, and 5 wt% MWCNTs, and CB-HIPS containing 17 wt% CB. Electrical characteristics are evaluated by measuring the surface resistance using a 4-point probe. Wear characteristics are evaluated using the reciprocating wear test, and a chrome steel ball with a curvature of 6.3 mm is used as the counterpart. The results show that the addition of MWCNTs or CB can improve the electrical and wear characteristics of HIPS composites. In the case of MWCNT-HIPS composites, surface resistance, friction coefficient, and specific wear rate decrease as the concentrations of MWCNTs increase. Moreover, the addition of MWCNTs is more effective in improving the electrical and wear characteristics of HIPS composites compared to the addition of CB. To fabricate the HIPS composite with appropriate electrical and wear characteristics, more than 4 wt% MWCNTs is added to HIPS.