Degradable low-density polyethylene

Degradable Low-Density Polyethylene (LDPE) Films. Typical xenon arc embrittlement times for unstabilized low-density polyethylene are l600-2UOO hrs. The controls chosen for this research are listed in Table II the thin LDPE garment bag embrittled in 1820 hr and the EcoPlastics LDPE control became brittle after 2075 hr xenon irradiation. The thin garment bag was not brittle, as determined by a fold test, after 18 months outdoor exposure. The Dupont "Sclair" LDPE control listed in Table II was unusual since it had short embrittlement times of 1175 hr in the Weather-Ometer and 6.5 months outdoors. This film was used as a yardstick to measure the Degradable LDPE films since a Degradable Plastic should not last more than 6 months, perhaps less, outdoors and 1200 hr in the xenon arc Weather-Ometer. 

Shear degradation is another parameter that is very difficult to quantify and it is not fully understood. Several studies have been made on this subject (16-19) and the topic has been reviewed (20). We have found in our own work (21) that NBS 1476, a low-density polyethylene, is very susceptible to shear degradation in the GPC column and that the amount of degradation that will occur is very dependent on both flow rate and the particle size of the packing. 

For a ToF-SIMS investigation of the surface oxidative degradation of low-density polyethylene (LDPE), the polymer was exposed to 1802 rather than 1602 in order to be able to readily discriminate oxygen introduced by the ageing process from that in the polymer prior to ageing [102], Figure 36 shows an example series of ToF-SIMS spectra from this investigation, which shows the clear separation of the lsO species from the lsO species. In the study, close correlation was observed between the intensity of the lsO carbonyl species determined by mid-infrared spectroscopy with the ToF-SIMS 180- peak intensity as a function of 1802 exposure time. ToF-SIMS spectra obtained from microtomed cross-sections showed no... 

The most fundamental work on polyethylene degradation is being done by A. C. Albertsson in Sweden(27,28,29,30,31) using elegant science with labelled polymers to measure the rate and quantity of carbon dioxide evolution from buried high and low density polyethylene films. Degradation occurs at about... 

F.S. Qureshi, M.B. Amin, A.G. Maadhah, and S.H. Hamid, Weather-induced degradation of linear low density polyethylene Mechanical properties. Polym. Plast. Tech. Eng., 28 (7 8), 649-662 (1989). 

McNeill, I.C. and Mohammed, M.H., A comparison of the thermal degradation behaviour of ethylene-ethyl acrylate copolymer, low density polyethylene and poly(ethyl acrylate), Polym. Deg. Stab., 1995,48, 175-187. 

Andersson, T., Holmgren, M. H., Nielsen, T., and Wesslen, B. (2005). Degradation of low density polyethylene during extrusion. IV. Off-flavor compounds in extruded films of stabilized LDPE. J. Appl. Polym. Sci. 95,583-595. 

Jana RN, Mukunda PG, Nando GB (2003) Thermogravimetric analysis of compatibi-lized blends of low density polyethylene and poly(dimethyl siloxane) rubber. Poly Degrad Stabil 80(l) 75-82... 

Zitting A, Savolainen H. 1979. Neurotoxic effects of the oxidative thermal degradation products from low density polyethylene. Fire Mater 3 80-83. 

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