Polyolefins food-packaging

Here we report the use of a readily prepared polymer immobilised TEMPO as a catalyst for alcohol oxidations.15 It was derived from a commercially available oligomeric, sterically hindered amine, poly[[6-[(l,l,3,3-tetramethylbutyl)amino]-l,3,5-triazine-2,4-diyl] [2,2,6,6-teramethyl-4-piperidinyl)-imino]-1,6-hexane-diyl[(2,2,6,6-tetramethyl-4-piperidinylimino]], better known as Chimassorb 944 (MW 3000 see figure 3 for structure). This compound is used as an antioxidant and a light stabiliser for plastics. It contributes significantly to the long-term heat stability of polyolefins and has broad approval for use in polyolefin food packaging.16... 

Methyl oleate Styrene/butadiene polymer extrusion aid, polyolefins food packaging Dimethicone copolyol extrusion copolymer, coatings Ethylene/methacrylic acid copolymer extrusion copolymer, film Ethylene/methacrylic acid copolymer extrusion copolymer, sheet Ethylene/methacrylic acid copolymer extrusion resin... 

As early as 1990, vitamin E has been considered an attractive substitute for other hindered phenolic antioxidants used in polyolefin food packaging, such as BHT [12]. The drawback of BHT and other hindered phenols was that oxidation products could leach into packaged food, causing an undesirable aftertaste. Vitamin E was considered a natural alternative to synthetic phenohc antioxidants used in food packaging [14]. Many smdies of vitamin E... 

J. Brandsch, P. Mercea, O. Piringer. Modeling of additive diffusion coefficients in polyolefins. Food Packaging Testing Methods and Applications, S.J. Risch editor, pp. 27-36, ACS Symposium Series Washington DC, 753 (2000). 

In particular, PB and PMP are inert materials and usually present no health hazard. PMP is employed extensively for a number of medical and food packaging appHcations. Several grades conform to FDA regulations and to the health standards of other countries. Flammability of polyolefin resins is equal to that of PP, around 2.5 cm /min (ASTM D635). However, during combustion or pyrolysis, smoke, fumes, and toxic decomposition products are formed and can pose a health hazard. 

Food packaging (electron-beam-irradiated polyolefins)... 

Table 10 contains some selected permeabiUty data including diffusion and solubiUty coefficients for flavors in polymers used in food packaging. Generally, vinyUdene chloride copolymers and glassy polymers such as polyamides and EVOH are good barriers to flavor and aroma permeation whereas the polyolefins are poor barriers. Comparison to Table 5 shows that the large molecule diffusion coefficients are 1000 or more times lower than the small molecule coefficients. The solubiUty coefficients are as much as one million times higher. Equation 7 shows how to estimate the time to reach steady-state permeation t if the diffusion coefficient and thickness of a film are known. 

Polybutylene It is a polyolefin used for cold and hot water piping. As a blown film it is used for food packaging. 

Multilayered materials can be readily formed using thermoforming including food packaging that may involve inclusion of layers of ethylene-vinyl alcohol copolymers, PS, polyolefins, and/or copolymers of vinylene dichloride and vinyl chloride. Microwavable food trays from (crystallized) PET are manufactured using thermoforming. 

No amount of sterilization wiU prevent or even slow autooxidation, and there are only two defenses removal of O2 and addition of inhibitors. Oxygen barriers in food packaging are a major topic in the engineering of polymer films. The barrier properties of various polymers are very important in food applications, and many of these are multilayer polymers that have a thin layer of an impermeable polymer (such as polyacrylonitrile and ionic polymers) on a cheaper but O2-permeable polymer such as a polyolefin, which gives mechanical strength to the fikn. 

This class of materials includes the family of plastics based on ethylene and propylene (Robertson, 2006). Low, linear, and high density PE and polypropylene (PP) materials are common food packaging materials. The use of polyolefins, such as PE and PE terephthalate (PETE) in contact with foods and beverages is common. However, contact with foods, especially under conditions of heat or long duration, can potentially impact sensory characteristics of the contained product. Packaging should be carefully selected, especially for applications that involve heat treatment at high temperatures while in contact with foods. 

Torri, L., Piergoiovanni, L., and Caldiroli, E. (2008). Odour investigation of granular polyolefins for flexible food packaging using a sensory panel and an electronic nose. Food Addit. Contain. 25(4), 490-502. 

Jabarin, S.A., Kollen, W.J., Polyolefin Properties for Rigid Food Packaging. Polymer Engineering and Science, 1988,28(18) 1156-1161. 

Most of the detailed systematic migration studies performed before 1990 were at low temperatures, i.e., less than 60 °C. In 1990, migration of antioxidants from polyolefins (the most common food packaging material) to the food simulants com oil, 95 % ethanol, water, 8 % ethanol and food was studied at high temperatures in the range... 

Most currently available diffusion coefficient data are for polyolefins. Appendix I provides a comprehensive list of Devalues taken from the scientific literature for LDPE, HDPE and PP. The diffusion data presented in the three tables of Appendix I were critically (i.e. not based on subjective decisions) selected from several hundreds of papers and reports published over the last four decades. A similar publication, but with far less data, was published more than 15 years ago (Flynn, 1982). In comparison with Flynn (1982) the criteria used to select the data in Appendix I were primarily based on considerations linked to relevance of the data for predicting migration into and from food packaging made from these polymers. The inclusion of experimental diffusion data in the present collection required that ... 

---