วารสารปี-40-ฉบับที่-4-resize

กฎหน้าต่างสามเหลี่ยมส� ำหรับขยายขนาดก� ำลังการผลิตวัสดุเชิงประกอบของพอลิโพรพิลีนและท่อคาร์บอนนาโนเพื่อการน� ำไฟฟ้า 94 The Journal of the Royal Society of Thailand Volume 40 Number 4 Oct-Dec 2015 Abstract Triangle Rule for Operating Windows and Scale-up Criteria for Volume Resistivity of PP/Carbon Nanotubes Composites Somsak Damronglerd Fellow of the Academy of Science, The Royal Society, Thailand Department of Chemical Technology, Faculty of Science, Chulalongkorn University, Bangkok Wareerom Polrat Department of Chemical Technology, Faculty of Science, Chulalongkorn University, Bangkok Winyu Tanthapanichakoon Thaipolyethylene Company Limited, Rayong Butra Boonliang Thaipolyethylene Company Limited, Rayong This study dealt with operating windows and scale-up rules of a compounding twin screw extruder for polypropylene (PP)/multi-walled carbon nanotubes (MWCNT) composites with required conductivity. In this study we show that the experimentally obtained boundary line separating either conductive or non-conductive region is essentially linear, and thus the operating windows, in which the PP/MWCNT composite is consistently conductive with statistically 95% reliability level, can be drawn as a triangle rule of the operating windows to achieve required volume resistivity as proposed. With a similar length to diameter ratio (L/D) and screw configuration between small (laboratory-scale) and large (production-scale) extruders, our investigation reveals that the most effective scale-up factors for volume resistivity are (D large /D small ) for the throughput, and (D small /D large ) for the screw speed as a new scale-up rule generally valid for any machine size. Keywords : triangle rule for operating windows, composite, polypropylene, carbon nanotube, twin screw extruder