Polypropylene biodegradation

Starch-Modified Polypropylene Biodegradable thermoplastic starch-grafted polypropylene. 

Sermanni, G.G. (1993). Isotactic polypropylene biodegradation by a microbial community Physico-chemical characterization of metabolites produced. Appl. Environ. Microbiol. 59 3695-3700, ISSN 0099-2240. 

Byrom D (1991) Miscellaneous biomaterials. In Byrom D (ed) Biomaterials novel materials from biological sources. Macmillan, New York, pp 335-359 Cacciari I, Quatrini P, Zirletta G, Mincione E, Vinciguerra V, Lupattelli P, Sermanni GG (1993) Isotactic polypropylene biodegradation by a microbial community physicochemical characterization of metabolites produced. Appl Environ Microbiol 59 3695-3700 Caldwell DE, Lawrence JR (1986) Growth kinetics of Pseudomonas fluorescens microcolonies within the hydrodynamic boundary layers of surface microenvironments. Microb Ecol 12 299-312... 

Pandey and Singh [60] have recently shown that polypropylene biodegrades much more rapidly than polyethylene by mass loss in compost. This was carried out on solvent extracted polymers to remove antioxidants and PP lost over 60% mass in 6 months whereas LDPE lost about 10% in the same time. Ethylene-propylene co-polymers biodegraded at rates intermediate between PP and PE. As expected, prior UV irradiation (photooxidation) increased both the rate and extent of the bioassimilation. This is fully in... 

Whereas polyetheylene, polypropylene, and polystyrene are virtually non-biodegradable, only specially modified, not widely employed, polyamides and polyurethanes are susceptible to biodegradation [2]. Consequently, the use... 

These monomers are biodegradeable and used for the production of bioplastics. PHAs produced from the process are usually composed of 100-30,000 monomers and exist in a short chain. Naturally, the properties of PHAs are similar to thermoplastics that are obtained from petrochemical industry such as polypropylene (PP) and polyethylene (PE) as shown in Table 1 (Evan and Sikdar, 1990). 

One of the main barriers to the widespread use of biodegradable plastics is their higher production cost compared to petroleum plastics. For example, whereas the cost of most commodity plastics, such as polypropylene, is well below 1 US /kg, the costs of some of the cheapest biodegradable plastics on the... 

Hot melt adhesives based on poly(3HB-co-3HV) have also been described [119]. Hot melts are commonly used in bookbinding, bag ending and case and carton sealing and are mostly based on synthetic materials such as polyethylene, polypropylene ethylene-vinyl acetate and styrene block copolymers [119]. Hot melts based on PHAs alleviate the dependence on petroleum based materials and allow the development of biodegradable alternatives based on natural raw materials. 

Fang X, Yang S, Chen L (1994) Synthesis and biodegradation of polypropylene ethylene carbonate. Gongneng Gaofenzi Xuebao 7 143-147... 

LDPE), polypropylene (PP), poly(vinyl chloride) (PVC), and polyethylene tere-phthalate (PET) [48], completely new areas of application are preferred in which biodegradability is required for admission, such as applications in the medical field [50, 51]. The reason for this is obvious. When new materials enter the market, they are in competition with aheady established materials. In the case of PUB, due to its temperature stability, a competition with poly(olefin)s arises for all applications in which biodegradabUity is not required by law (Fig. 12). 

PHAs can consist of a diverse set of repeating unit structures and have been studied intensely because the physical properties of these biopolyesters can be similar to petrochemical-derived plastics such as polypropylene (see Table 1). These biologically produced polyesters have already found application as bulk commodity plastics, fishing lines, and for medical use. PHAs have also attracted much attention as biodegradable polymers that can be produced from biorenewable resources. Many excellent reviews on the in vivo or in vitro synthesis of PHAs and their properties and applications exist, underlining the importance of this class of polymers [2, 6, 7, 12, 26-32]. 

Preparation of biodegradable salts derived from the reaction product of polypropylene ether amines and bis(perfluorobutylsulfonyl)-imine for use as antistatic agents. 

The biodegradation of poly(alkylene glycols) is hindered by their lack of water solubility, and only the low oligomers of polypropylene glycol) are biodegradable with any certainty (179—181), as are those of poly(tetramethylene glycol) (182). A similar exo-oxidation mechanism to that reported for poly(ethylene glycol) has been proposed. 

Propylene oxide represents a very attractive epoxide monomer for copolymerization with C02, as polypropylene carbonate) is industrially valuable. The low glass transition temperature (Tg) of 313 K, the sharp and clean decomposition above 473 K, and biodegradability of this copolymer are the reasons for its attracting interest in several applications. On a similar basis, H NMR spectroscopy is useful for assessing the coupling products resulting from the reaction of PO and C02 (Figure 8.21). 

Disposables are also considered to be an environmental threat. Only some of the materials used in the diapers are biodegradable (the wood pulp and SAP). The polyethylene and polyester sheets are not biodegradable neither is the elastic used for better fit, nor the polypropylene used for the tape that is employed as a fastener. Disposable diapers account for up to 2 percent of the total volume of landfills in the United States. The lifetime of the diaper in the landfill depends on several environmental factors soil condition, groundwater flow, and the presence of other materials in the soil. see also Matertals Science Polymers, Synthetic. 

For economic reasons, regenerated cellulose has been replaced recently or is in serious competition with polypropylene films in many applications. Regenerated cellulose has the advantage that it biodegrades well in composting. 

In the presence of limited nutrients, bacteria can be induced to make polyhy-droxybutyrates and valerates, which are processed into a copolymer known as Biopol . Biopol has properties similar to polypropylene, but it is biodegradable and obtained from nonpetroleum sources. 

At the moment, there are a growing number of biodegradable polymers performing well in niche applications. Many of these materials can be even more cost competitive in the future compared to petroleum-based resins including PET, polyethylene (PE), and polypropylene (PP) as suppliers develop better material properties that can lead to thinner films or lower processing costs. 

In 2004, RPC Bebo Nederland launched a range of biodegradable containers manufactured in NatureWork s PLA material. RPC says that PLA offers excellent clarity and has an equivalent oxygen barrier to polypropylene. For sealed packs, RPC Bebo Nederland can also supply a heat-sealable, compostable lidding film, which is manufactured from biodegradable cellulose derived from wood pulp. 

Biodegradable polymers are similar in terms of their chemical structure to conventional thermoplastics such as polyethylene, polypropylene and polystyrene. They can be processed using standard polymer processing methods such as film extrusion, injection moulding and blow moulding. 

Biodegradation-resistant polymers have the opposite characteristics and—unsurprisingly—are used to make the stronger, more durable polymers. Oxygen-free polymers such as polypropylene and polyethylene resist biodegradation entirely. 

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