Prooxidants polyethylene films

Koutny M, Lemaire J, Delort A-M. Biodegradation of polyethylene films with prooxidant additives. Chemosphere 2006 64 1243-1252. 

Starch can be used as a natural filler in traditional plastics [11,22-32] and particularly in polyolefins. When blended with starch beads, polyethylene films [33] biodeteriorate on exposure to a soil environment. The microbial consumption of the starch component, in fact, leads to increased porosity, void formation, and the loss of integrity of the plastic matrix. Generally [31,34-37], starch is added at fairly low concentrations (6-15%) the overall disintegration of these materials is achieved by the use of transition metal compounds, soluble in the thermoplastic matrix, as prooxidant additives which catalyse the photo- and thermooxidative process [38-41]. An example of the contribution of starch in promoting the disintegration of photodegradable low density polyethylene (LDPE) is shown in Figs. 6.1 and 6.2 [42,43]. 

Table 1. Total luminescence intensisty (TLl) and carbonyl index for polyethylene films containing Fe(Il)-stearate and polyoctylene (PE-MO), Fe(ll)-stearate (PE-M) or a commercial prooxidant system (PE-A) aged in air at 80 C.

ECO copolymer refers to sheets (0.42 mm) of enhanced-photodegradable polyethylene used in commercial photodegradable six-pack rings and was supplied by ITW HiCone Ltd (Chicago, IL). Polyethylene/MX refers to films (0.03 mm) of polyethylene containing iron compounds as prooxidant additive and was supplied by Plastigone Inc. of Miami, FL. 

Starch-filled polyethylenes containing prooxidants are commonly used in agricultural mulch film, in bags and in six-pack yoke packaging. Commercial products based on this technology are sold by Ecostar and Archer Daniels... 

Chromatographic fingerprinting and total luminescence intensity anivsis The studied materials were 15 pm films of polyethylene, three of the films contained prooxidants, 1) 10% Fe(II)-stearate master batch, 2) 10% Fe(II)-stearate master batch and 10% polyoctylene, and 3) 7.5% Ampacet MB, a commercial prooxidant Hie amount of Ampacet MB was chosen to get the same amount of iron as in the Fe(II)-stearate master batch. The films were kindly provided by Tenova AB. Degradation of the films were performed in open containers in air at 80 The processing and analyses are described in more... 

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