New developments on the ring opening polymerisation of polylactide
نویسندگان
چکیده
Polylactides (PLA), biodegradable aliphatic polyesters, produced solely from renewable resources may substitute petrochemically based polymers in a broad range of applications in the near future, if we manage to produce them at lower cost and higher efficiency as nowadays. Possible applications include food packaging for meat and soft drinks, films for agro-industry and non-wovens in hygienic products. The authors developed, based on a new catalytic system, a reactive extrusion polymerisation process, which can be used to produce PLA continuously in larger quantities and at lower costs than before. This extrusion polymerisation process has been developed and tested with laboratory scale machines and the possibilities to extend this polymerisation process to lactide based blockcopolymers have been investigated. © 2000 Elsevier Science B.V. All rights reserved.
منابع مشابه
Nacnac(Bn)MgOtBu: a diketiminate-based catalyst for the polymerisation of rac-lactide with slight isotactic preference.
The reaction of N,N'-dibenzyl-2-amino-4-imino-pent-2-ene, nacnac(Bn)H, with 1 or 2 equiv. of MgnBu₂ afforded the homoleptic complex nacnac(Bn)₂Mg. The reaction of nacnac(Bn)H with Mg(N(SiMe₃)₂)₂ yielded nacnac(Bn)MgN(SiMe₃)₂, which reacted with tert-butanol to form nacnac(Bn)MgOtBu. The latter complex crystallizes as an alkoxide bridge dimer and is active in the ring-opening polymerisation of r...
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The increasing shortage of resources has enforced the search for production techniques for biodegradable polymers made of renewable raw materials. An example is polylactide (PLA), an aliphatic polyester, which can be obtained by the metal-catalysed ring-opening polymerisation (ROP) of lactide (Fig. 1). The monomer for PLA production is available from corn or sugar beets by a bacterial fermentat...
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