Broadened foaming scope of iPP adjusted by its self-enhancement and nucleating agent under compressed CO2

Abstract The melt strength and cell nucleating ability of isotactic Polypropylene (iPP) were obviously improved, in the presence of structured melt and a low loading nucleating agent DMDBS. Rheological testing results indicated that a storage modulus of about ∼10 5 to ∼10 6 Pa of iPP and iPP/ 0.2DMDBS at the temperatures which near to iPP’s melting point, could be benefit to generate ideal microcellular foams with cell density up to ∼10 12 cells/cm 3 . The broadened T/P (Temperature/Pressure) batch foaming windows of iPP and iPP/0.2DMDBS were sketched out. With the increasing pressure, the temperature window could be broadened, a 63℃ expanded temperature span of iPP/ 0.2DMDBS could be achieved after foaming at 18MPa, while, that foamed at 6MPa is only 20℃. At a fixed saturation pressure and a temperature slightly below to iPP’s T m within the T/P window, comparatively fine iPP cells were fabricated.