an investigation into the physical properties of polyethylene gas pipes by the incorporation of anti-rodent masterbatches

the incorporation of several anti-rodent masterbatches into polyethylene (pe) granules used for gas pipes and the effects of the masterbatches on the physical properties of the pipes were studied. four commercial anti-rodent masterbatches from different international companies including, clariant, alchemix, polyone, and newgen were used in this research. each of the masterbatch was primarily dry-blended with pe granules by a laboratory-scale tumbling mixer. the concentration of anti-rodent masterbatches used in the pe blends was fixed according to the recipe recommended by the producers as 1, 2.5, 3, and 4 phr for the masterbatches of clarian, alchemix, polyone, and newgen respectively. pe granules and masterbatch blends were separately fed into the hopper of a pipe extruder and a length of a hundred and fifty meters of the pipe with the outside diameter (o.d.) of 25 millimeters was continuously produced for each anti-rodent-added pe compound. two groups of experiments were planned for this investigation; laboratory experiments including impact resistance, tensile elongation, environmental stress cracking (escr), melt flow rate (mfr), and differential scanning calorimetry (dsc) were carried out on the control (anti-rodent free) and anti-rodent-added pe100 test samples prepared in the laboratory. also, a group of factory tests such as burst, hydrostatic (100, 165, and 1000 hr), slow crack growth (scg), and oxygen induction time (oit) were performed on the control and anti-rodent-added pipe samples.