Abiotic degradation products from enhanced environmentally degradable polyethylene

Abstract

Abiotic degradation products from LDPE with starch + pro-oxidant, LDPE with starch only and pure LDPE were determined as a step towards establishing products resulting from environmental degradation. The samples were subjected to thermal ageing in water at 95°C for 6 weeks or alternatively pre-heated and subsequently immersed in aqueous environments at ambient temperature for 10 months whereafter the water phase was analyzed for degradation products. Altogether over 50 degradation products were identified by GC-MS, mainly ketones, alcohols, aldehydes, lactones and carboxylic acids, the last being most represented. The amount of degradation products formed from the different samples correlated to their molecular weight reductions as measured by SEC but was also dependent on the permeability of the sample, i.e. its ability to allow formed degradation products to diffuse out to the surrounding environment. The addition of both starch and pro-oxidant significantly increased the susceptibility to degradation, while the addition of starch alone gave a noticeable but smaller increase.

Degradation of enhanced environmentally degradable polyethylene in biological aqueous media: Mechanisms during the first stages

“…Samples without these additives were used as a control (referred to as pure LDPE in the text ) . The prodegradant additives were introduced into the LDPE matrix in the form of a master batch (MB) in the amounts of 10,15, and 20%. The master batch consisted mainly of corn starch, LLDPE, styrene-butadiene copolymer ( SBS ) and manganese stearate.…”

Behavior of Polyethylene Films in Soil

“…A great number of references deal with polyethylene and polypropylene degradation. A systematic study of polyethylene degradation mechanism was carried out by Albertsson et al [3][4][5][6][7][8][9]. Koutny et al summarize the findings on mechanism and degradation of polyethylene giving an extensive literature survey [10].…”

Comparative study on the effects of galbanic acid, galbanic ferric salt and tetrabromo galbanic acid on photo-oxidative degradation of linear low density (LLDPE) films

“…The magnitude of the discarded PE packages has led us to find new methods of making this polymer biodegradable. The most common approaches include introducing keton carbonyl groups into the polymer chain [4][5][6] or mix it with suitable additives (sensitizers) which absorb the ultraviolet of sun-rays and generate reactive chemical intermediates which facilitate disintegration and photo-oxidation of the polymer [7]. The fundamental processes which occurs in the photo-oxidation of polyethylene have been extensively studied [8,9].…”

“…The main objective of the present work is to prove the double bond existing in the substituted moiety of GA (C 4 =C 5 ) is the center of photo-activity of this additive and second to check if photoactivity of GA is enhanced by converting it to ferric salt, keeping in mind that iron salt of organic compounds act as highly strong photo sensitizer in PE [7,8,14]. The laboratory procedures used for preparation of Br-GA and Fe-GA compounds would be included.…”