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Ian Manners - One of the best experts on this subject based on the ideXlab platform.
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role of torsional strain in the Ring Opening Polymerisation of low strain n nickelocenophanes
Chemical Science, 2019Co-Authors: Rebecca A Musgrave, Ian Manners, Rebekah L N Hailes, Vincent T AnnibaleAbstract:Ring-Opening Polymerisation (ROP) of strained [1]- and [2]metallocenophanes and related species is well-established, and the monomer Ring-strain is manifest in a substantial tilting of the cyclopentadienyl ligands, giving α angles of ∼14–32°. Surprisingly, tetracarba[4]nickelocenophane [Ni(η5-C5H4)2(CH2)4] (2) undergoes ROP (pyridine, 20 °C, 5 days) to give primarily insoluble poly(nickelocenylbutylene) [Ni(η5-C5H4)2(CH2)4]n (12), despite the lack of significant Ring-tilt. The exoenthalpic nature of the ROP was confirmed by DFT calculations involving the cyclic precursor and model oligomers (ΔH0ROP = −14 ± 2 kJ mol−1), and is proposed to be a consequence of torsional strain present in the ansa bridge of 2. The similarly untilted disila-2-oxa[3]nickelocenophanes [Ni(η5-C5H4)2(SiMe2)2O] (13) and [Ni(η5-C5H4)2(SiMePh)2O] (14) were found to lack similar torsional strain and to be resistant to ROP under the same conditions. In contrast, 1-methyltricarba[3]nickelocenophane {Ni(η5-C5H4)2(CH2)2[CH(CH3)]} (15) with a significant tilt angle (α ∼ 16°) was found to undergo ROP to give soluble polymer {Ni(η5-C5H4)2(CH2)2[CH(CH3)]}n (18). The reversibility of the process in this case allowed for the effects of temperature and reaction concentration on the monomer–polymer equilibrium to be explored and thereby thermodynamic data to be elucidated (ΔH0ROP = −8.9 kJ mol−1, ΔG0ROP = −3.1 kJ mol−1). Compared to the previously described ROP of the unsubstituted analogue [Ni(η5-C5H4)2(CH2)3] (1) (ΔH0ROP = −10 kJ mol−1, ΔG0ROP = −4.0 kJ mol−1), the presence of the additional methyl substituent in the ansa bridge appears to marginally disfavour ROP and leads to a corresponding decrease in the equilibrium polymer yield.
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Ring Opening Polymerisation of low strain nickelocenophanes synthesis and magnetic properties of polynickelocenes with carbon and silicon main chain spacers
Chemistry: A European Journal, 2019Co-Authors: Rebekah L N Hailes, Ian Manners, Rebecca A Musgrave, Gr Whittell, Alexander F R Kilpatrick, Andrew D Russell, Dermot OhareAbstract:Polymetallocenes based on ferrocene, and to a lesser extent cobaltocene, have been well-studied, whereas analogous systems based on nickelocene are virtually unexplored. It has been previously shown that poly(nickelocenylpropylene) [Ni(η5 -C5 H4 )2 (CH2 )3 ]n is formed as a mixture of cyclic (6x ) and linear (7) components by the reversible Ring-Opening Polymerisation (ROP) of tricarba[3]nickelocenophane [Ni(η5 -C5 H4 )2 (CH2 )3 ] (5). Herein the generality of this approach to main-chain polynickelocenes is demonstrated and the ROP of tetracarba[4]nickelocenophane [Ni(η5 -C5 H4 )2 (CH2 )4 ] (8), and disila[2]nickelocenophane [Ni(η5 -C5 H4 )2 (SiMe2 )2 ] (12) is described, to yield predominantly insoluble homopolymers poly(nickelocenylbutylene) [Ni(η5 -C5 H4 )2 (CH2 )4 ]n (13) and poly(tetramethyldisilylnickelocene) [Ni(η5 -C5 H4 )2 (SiMe2 )2 ]n (14), respectively. The ROP of 8 and 12 was also found to be reversible at elevated temperature. To access soluble high molar mass materials, coPolymerisations of 5, 8, and 12 were performed. Superconducting quantum interference device (SQUID) magnetometry measurements of 13 and 14 indicated that these homopolymers behave as simple paramagnets at temperatures greater than 50 K, with significant antiferromagnetic coupling that is notably larger in carbon-bridged 6x /7 and 13 compared to the disilyl-bridged 14. However, the behaviour of these polynickelocenes deviates substantially from the Curie-Weiss law at low temperatures due to considerable zero-field splitting.
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polymeric materials based on main group elements the recent development of ambient temperature and controlled routes to polyphosphazenes
Dalton Transactions, 2008Co-Authors: Vivienne Blackstone, Alejandro Presa Soto, Ian MannersAbstract:This Perspective discusses the development of new routes to polyphosphazenes, [R2PN]n, that occur at ambient temperature and, in some cases, allow molecular weight control and access to narrow molecular weight distributions and block copolymers. For example, the room temperature silyl-carborane initiated Ring-Opening Polymerisation of (NPCl2)3 is described together with chain growth condensation Polymerisations of phosphoranimines Cl3PNSiMe3 and BrMePhPNSiMe3. Recent works on donor-stabilised cationic phosphoranimines are also discussed.
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ambient temperature Ring Opening Polymerisation rop of cyclic chlorophosphazene trimer n3p3cl6 catalyzed by silylium ions
Chemical Communications, 2008Co-Authors: Yun Zhang, Keith Huynh, Ian Manners, Christopher A ReedAbstract:The temperature required for Ring-Opening Polymerisation of cyclo-N(3)P(3)Cl(6) can be dramatically lowered by employing trialkylsilylium carboranes [R(3)Si(CHB(11)X(11)] as catalysts.
Antoine Buchard - One of the best experts on this subject based on the ideXlab platform.
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DFT study of the polycondensation and Ring-Opening Polymerisation of novel limonene-derived lactone and bifunctional alcohol/carboxylic acid monomers
2018Co-Authors: Antoine BuchardAbstract:Data to support article: New renewably-sourced polyesters from limonene-derived monomers DOI: 10.6084/m9.figshare.6957368 Journal: Green Chemistry, 2018, DOI: 10.1039/C8GC02957A Authors: Megan R. Thomsett,a Jonathan C. Moore,a Antoine Buchard,b Robert A. Stockman*a and Steven M. Howdle*a. School of Chemistry, University Park, University of Nottingham, Nottingham, NG7 2RD, UK. E-mail: robert.stockman@nottingham.ac.uk; Fax: +44 (0)115 951356b. Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK DFT study: - The DFT optimised geometries and computed free enthalpies of various limonene derived alcohol-carboxylic acids and their different possible dimers formed by polycondensation, as well as a related lactone and its Ring-opened products. - The thermochemistry of the reaction of lactonisation of alcohol/carboxylic acid 6a.- The thermochemistry of the Ring-Opening of lactone 4 by benzyl alcohol.- The thermochemistry of the isodesmic reaction between lactone 4 and isopropylisopropanoate.- The thermochemistry of the condensation (all combination possible) between bifunctional alcohol/carboxylic acid 6a and 6b, to yield a dimeric ester, as a model for Polymerisation. Protocol: rM06-2X/6-311++g(2d,p)/cpcm=ethylethanoate/T=298.15K or 453.15K Content: - Gaussian09 rev D.01 output files- Computational_full_details_and_results.pdf
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co2 driven stereochemical inversion of sugars to create thymidine based polycarbonates by Ring Opening Polymerisation
Polymer Chemistry, 2017Co-Authors: Georgina L Gregory, Elizabeth M Hierons, Gabriele Kociokkohn, Ram I Sharma, Antoine BuchardAbstract:The development of biodegradable polymers from renewable resources is vital in addressing the dependence of plastics on petroleum-based feedstocks and growing ocean and landfill waste. Herein, both CO2 and natural sugar diols are utilised as abundant, safe and renewable building blocks for the synthesis of degradable and biocompatible aliphatic polycarbonates. Despite a strong potential for advanced polymer properties, inspired by Nature's supramolecular base-paiRing, polycarbonates from the sugar components of DNA, 2′-deoxyribonucleosides have been limited by the inability of phosgene derivatives to form the cyclic carbonate monomers that would allow for controlled Ring-Opening Polymerisation. CO2 insertion at 1 atm pressure into methylated thymidine 2′-deoxyribonucleoside, facilitated by organic base 1,8-diazabicyclo-[5.4.0]-undec-7-ene, affected an intramolecular SN2-like displacement of a tosyl leaving group to yield the cyclic carbonate by stereochemical inversion. Organocatalytic Ring-Opening Polymerisation proceeded rapidly in solution resulting in high monomer conversions of 93% and number-average molecular weights, substantially greater and more controlled than via polycondensation routes. The thermodynamic parameters of the Polymerisation (ΔHp = −12.3 ± 0.4 kJ mol−1 and ΔSp = −29 ± 1.1 J mol−1 K−1) were determined from the equilibrium monomer conversions over a temperature range of 0 to 80 °C and pseudo-first order kinetics demonstrated. The amorphous thymidine-based polycarbonates exhibited high glass transition temperatures of 156 °C and were found to be highly degradable to the constituent diol under basic aqueous conditions. Static water contact angle measurements and cell studies with MG-63 cell line indicated slightly hydrophilic and biocompatible materials, promising for tissue-engineeRing applications. The novel, CO2-driven approach to cyclic carbonate synthesis represents a means of expanding the scope of sugar-based monomers for tailored material properties derived from natural products.
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polymers from sugars cyclic monomer synthesis Ring Opening Polymerisation material properties and applications
Chemical Communications, 2017Co-Authors: Georgina L Gregory, Eva M Lopezvidal, Antoine BuchardAbstract:Plastics are ubiquitous in modern society. However, the reliance on fossil fuels and the environmental persistence of most polymers make them unsustainable. Scientists are facing the challenge of developing cost-effective and performance-competitive polymers from renewable resources. Carbohydrates are a renewable feedstock with tremendous potential: sugars are widely available, environmentally benign and are likely to impart biocompatibility and degradability properties to polymers due to their high oxygen content. Sugars are also a feedstock with great structurally diversity and functionalisation potential that can enable fine tuning of the resulting polymer properties. In recent years, Ring-Opening Polymerisation (ROP) has emerged as the method of choice for the controlled Polymerisation of renewable cyclic monomers, in particular lactones and cyclic carbonates, to allow the precise synthesis of complex polymer architectures and address commodity and specialist applications. This feature article gives an overview of sugar-based polymers that can be made by ROP. In particular, recent advances in the synthetic routes towards monomers that preserve the original carbohydrate core structure are presented. The performances of various homogeneous catalysts and the properties of the resultant polymers are given, and future opportunities highlighted for the development of both the materials and catalysts.
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DFT study of the reaction between TBD, benzylalcohol initiator, and one molecule of alpha/beta-methoxy-2-deoxy-D-ribose cyclic carbonate, or of trimethylene carbonate (Ring-Opening Polymerisation initiation step)
2017Co-Authors: Antoine Buchard, Georgina L GregoryAbstract:Data to support article:Polymers from sugars and CO2: Ring-Opening Polymerisation and coPolymerisation of cyclic carbonates derived from 2-deoxy-ᴅ-riboseDOI: 10.6084/m9.figshare.4644574Authors:Georgina L. Gregory,a Gabriele Kociok-Köhna and Antoine Bucharda,*a Department of Chemistry, University of Bath, Bath BA2 7AY- DFT optimised geometries and computed free enthalpies of local minima (intermediates) and local maxima (transition states) were used to investigate the mechanism of the reaction between TBD, benzyl alcohol and 1 molecule of alpha or beta-methoxy-2-deoxy-D-ribose cyclic carbonate cyclic carbonate to account for the initiation step of Ring-Opening Polymerisation. Protocols:rwB97XD/6-311++G(d,p)/6-31+G(d)cpcm=dichloromethane/T=298.15KContent:- Gaussian09 rev D.01 output files- ROP_initiation.pdf, illustrating the calculations made and summarising the free enthalpies computed
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Polymers from sugars and CO2: Ring-Opening Polymerisation and coPolymerisation of cyclic carbonates derived from 2-deoxy-D-ribose
Polymer Chemistry, 2017Co-Authors: Georgina L Gregory, Gabriele Kociok-köhn, Antoine BuchardAbstract:Bio-based aliphatic polycarbonates (APCs) are attractive synthetic materials for biomedical applications because of their biodegradabilty and biocompatability properties. A high yielding 3-step process that utilises CO2 as a C1 synthon is presented for converting raw sugar, 2-deoxy-D-ribose into a novel 6-membered cyclic carbonate for Ring-Opening Polymerisation (ROP) into carbohydrate-based APCs. The α- and β-anomers of the monomer could be isolated and revealed very different polymerisability, as rationalised by DFT calculations. Whereas the β-anomer could not be polymerised under the conditions tested, organocatalytic homoPolymerisation of the α-anomer, in solution at room temperature (rt) or under melt conditions, yielded highly insoluble polycarbonates, composed of both cyclic and linear topologies, and exhibiting a glass transition temperature (Tg) of ∼58 °C. Random copolymers with controllable incorporation of this new sugar monomer were prepared with trimethylene carbonate (TMC) at rt in the bulk or in solution with Mn up to 64000 g mol−1. With increasing sugar content, the Tg values of the copolymers increased and their thermal degradability was enhanced, giving access to a new class of APCs with tailored properties.
Andrew P Dove - One of the best experts on this subject based on the ideXlab platform.
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photoinduced Ring Opening Polymerisation of l lactide via a photocaged superbase
Chemical Communications, 2018Co-Authors: Paula K Kuroishi, Andrew P DoveAbstract:The phototriggered Ring-Opening Polymerisation of L-lactide is demonstrated for the first time using a photocaged tetramethylguanidine. The catalytic activity of the free guanidine was also investigated, showing it to be active for the Polymerisation of δ-valerolactone and e-caprolactone in the presence of a thiourea cocatalyst.
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benzyl bispidine as an efficient replacement for sparteine in Ring Opening Polymerisation
Chemical Science, 2013Co-Authors: Richard Todd, Sarah Tempelaar, Gabriel Rubio, Daniel J Hall, Andrew P DoveAbstract:The synthesis and application of a dibenzyl-functionalized bispidine, in combination with 1-(3,5-bis(trifluoromethyl)phenyl)-3-cyclohexylthiourea (TU) co-catalyst, has been demonstrated to be an excellent catalyst for the controlled Ring-Opening Polymerisation (ROP) of lactide and cyclic carbonate monomers. Notably, the Polymerisation proceeds with negligible transesterification or epimerisation, with the Polymerisation of stereopure L-lactide affording highly crystalline poly(lactide) with a Tm of 156 °C. ROP of racemic lactide results in the observation of a modest degree of stereocontrol such that the probability of isotactic enchainment, Pm = 0.74. Comparison of a range of alternative hydrogen bond donor co-catalysts revealed that TU displayed the highest Polymerisation rates in combination with the dibenzyl-functionalized bispidine.
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synthesis and post Polymerisation modifications of aliphatic poly carbonate s prepared by Ring Opening Polymerisation
Chemical Society Reviews, 2013Co-Authors: Sarah Tempelaar, Philippe Dubois, Laetitia Mespouille, Olivier Coulembier, Andrew P DoveAbstract:Owing to their low toxicity, biocompatibility and biodegradability, aliphatic poly(carbonate)s have been widely studied as materials for biomedical application. Furthermore, the synthetic versatility of the six-membered cyclic carbonates for the realization of functional degradable polymers by Ring-Opening Polymerisation has driven wider interest in this area. In this review, the synthesis and Ring-Opening Polymerisation of functional cyclic carbonates that have been reported in the literature in the past decade are discussed. Finally, the post-Polymerisation modification methods that have been applied to the resulting homopolymers and copolymers and the application of the materials are also discussed.
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development of amino oxazoline and amino thiazoline organic catalysts for the Ring Opening Polymerisation of lactide
Chemistry: A European Journal, 2010Co-Authors: Jan M Becker, Sarah Tempelaar, Matthew J Stanford, Ryan J Pounder, James A Covington, Andrew P DoveAbstract:The Ring-Opening Polymerisation of lactide by a range of amino oxazoline and amino thiazoline catalysts is reported. The more electron-rich derivatives are demonstrated to be the most highly active and Polymerisation is well controlled, as evidenced by the linear relationship between the molecular weight and both the monomer conversion and the monomer-toinitiator ratio. Mechanistic studies reveal significant interactions between the monomer, initiator and catalyst and that the Polymerisation is first order with respect to each of these components. These observations indicate that the Polymerisation operates by a general base/pseudo-anionic mechanism.
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stereocontrolled Ring Opening Polymerisation of lactide
Chemical Society Reviews, 2010Co-Authors: Matthew J Stanford, Andrew P DoveAbstract:The important advances and current trends in the stereocontrolled Ring-Opening Polymerisation of lactide are discussed in this tutorial review. Microstructures, structural characterisation methods and the properties of stereoregular poly(lactide)s are examined. The application of metal-based catalysts dominates this area although simple anionic Polymerisation and organocatalytic routes that demonstrate control of the polymer tacticity are discussed.
Georgina L Gregory - One of the best experts on this subject based on the ideXlab platform.
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co2 driven stereochemical inversion of sugars to create thymidine based polycarbonates by Ring Opening Polymerisation
Polymer Chemistry, 2017Co-Authors: Georgina L Gregory, Elizabeth M Hierons, Gabriele Kociokkohn, Ram I Sharma, Antoine BuchardAbstract:The development of biodegradable polymers from renewable resources is vital in addressing the dependence of plastics on petroleum-based feedstocks and growing ocean and landfill waste. Herein, both CO2 and natural sugar diols are utilised as abundant, safe and renewable building blocks for the synthesis of degradable and biocompatible aliphatic polycarbonates. Despite a strong potential for advanced polymer properties, inspired by Nature's supramolecular base-paiRing, polycarbonates from the sugar components of DNA, 2′-deoxyribonucleosides have been limited by the inability of phosgene derivatives to form the cyclic carbonate monomers that would allow for controlled Ring-Opening Polymerisation. CO2 insertion at 1 atm pressure into methylated thymidine 2′-deoxyribonucleoside, facilitated by organic base 1,8-diazabicyclo-[5.4.0]-undec-7-ene, affected an intramolecular SN2-like displacement of a tosyl leaving group to yield the cyclic carbonate by stereochemical inversion. Organocatalytic Ring-Opening Polymerisation proceeded rapidly in solution resulting in high monomer conversions of 93% and number-average molecular weights, substantially greater and more controlled than via polycondensation routes. The thermodynamic parameters of the Polymerisation (ΔHp = −12.3 ± 0.4 kJ mol−1 and ΔSp = −29 ± 1.1 J mol−1 K−1) were determined from the equilibrium monomer conversions over a temperature range of 0 to 80 °C and pseudo-first order kinetics demonstrated. The amorphous thymidine-based polycarbonates exhibited high glass transition temperatures of 156 °C and were found to be highly degradable to the constituent diol under basic aqueous conditions. Static water contact angle measurements and cell studies with MG-63 cell line indicated slightly hydrophilic and biocompatible materials, promising for tissue-engineeRing applications. The novel, CO2-driven approach to cyclic carbonate synthesis represents a means of expanding the scope of sugar-based monomers for tailored material properties derived from natural products.
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polymers from sugars cyclic monomer synthesis Ring Opening Polymerisation material properties and applications
Chemical Communications, 2017Co-Authors: Georgina L Gregory, Eva M Lopezvidal, Antoine BuchardAbstract:Plastics are ubiquitous in modern society. However, the reliance on fossil fuels and the environmental persistence of most polymers make them unsustainable. Scientists are facing the challenge of developing cost-effective and performance-competitive polymers from renewable resources. Carbohydrates are a renewable feedstock with tremendous potential: sugars are widely available, environmentally benign and are likely to impart biocompatibility and degradability properties to polymers due to their high oxygen content. Sugars are also a feedstock with great structurally diversity and functionalisation potential that can enable fine tuning of the resulting polymer properties. In recent years, Ring-Opening Polymerisation (ROP) has emerged as the method of choice for the controlled Polymerisation of renewable cyclic monomers, in particular lactones and cyclic carbonates, to allow the precise synthesis of complex polymer architectures and address commodity and specialist applications. This feature article gives an overview of sugar-based polymers that can be made by ROP. In particular, recent advances in the synthetic routes towards monomers that preserve the original carbohydrate core structure are presented. The performances of various homogeneous catalysts and the properties of the resultant polymers are given, and future opportunities highlighted for the development of both the materials and catalysts.
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DFT study of the reaction between TBD, benzylalcohol initiator, and one molecule of alpha/beta-methoxy-2-deoxy-D-ribose cyclic carbonate, or of trimethylene carbonate (Ring-Opening Polymerisation initiation step)
2017Co-Authors: Antoine Buchard, Georgina L GregoryAbstract:Data to support article:Polymers from sugars and CO2: Ring-Opening Polymerisation and coPolymerisation of cyclic carbonates derived from 2-deoxy-ᴅ-riboseDOI: 10.6084/m9.figshare.4644574Authors:Georgina L. Gregory,a Gabriele Kociok-Köhna and Antoine Bucharda,*a Department of Chemistry, University of Bath, Bath BA2 7AY- DFT optimised geometries and computed free enthalpies of local minima (intermediates) and local maxima (transition states) were used to investigate the mechanism of the reaction between TBD, benzyl alcohol and 1 molecule of alpha or beta-methoxy-2-deoxy-D-ribose cyclic carbonate cyclic carbonate to account for the initiation step of Ring-Opening Polymerisation. Protocols:rwB97XD/6-311++G(d,p)/6-31+G(d)cpcm=dichloromethane/T=298.15KContent:- Gaussian09 rev D.01 output files- ROP_initiation.pdf, illustrating the calculations made and summarising the free enthalpies computed
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Polymers from sugars and CO2: Ring-Opening Polymerisation and coPolymerisation of cyclic carbonates derived from 2-deoxy-D-ribose
Polymer Chemistry, 2017Co-Authors: Georgina L Gregory, Gabriele Kociok-köhn, Antoine BuchardAbstract:Bio-based aliphatic polycarbonates (APCs) are attractive synthetic materials for biomedical applications because of their biodegradabilty and biocompatability properties. A high yielding 3-step process that utilises CO2 as a C1 synthon is presented for converting raw sugar, 2-deoxy-D-ribose into a novel 6-membered cyclic carbonate for Ring-Opening Polymerisation (ROP) into carbohydrate-based APCs. The α- and β-anomers of the monomer could be isolated and revealed very different polymerisability, as rationalised by DFT calculations. Whereas the β-anomer could not be polymerised under the conditions tested, organocatalytic homoPolymerisation of the α-anomer, in solution at room temperature (rt) or under melt conditions, yielded highly insoluble polycarbonates, composed of both cyclic and linear topologies, and exhibiting a glass transition temperature (Tg) of ∼58 °C. Random copolymers with controllable incorporation of this new sugar monomer were prepared with trimethylene carbonate (TMC) at rt in the bulk or in solution with Mn up to 64000 g mol−1. With increasing sugar content, the Tg values of the copolymers increased and their thermal degradability was enhanced, giving access to a new class of APCs with tailored properties.
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DFT study of the thermodynamics of the reaction between dimethyl carbonate and alpha/beta-methoxy-2-deoxy-D-ribose or trimethylene cyclic carbonates
2017Co-Authors: Antoine Buchard, Georgina L GregoryAbstract:Data to support article:Polymers from sugars and CO2: Ring-Opening Polymerisation and coPolymerisation of cyclic carbonates derived from 2-deoxy-ᴅ-riboseDOI: 10.6084/m9.figshare.4644577Authors:Georgina L. Gregory,a Gabriele Kociok-Köhn,a and Antoine Bucharda,*a Department of Chemistry, University of Bath, Bath BA2 7AYDFT study:- DFT optimised geometries and computed enthalpies were used to calculate the thermodynamics of the isodesmic reactions between dimethyl carbonate and alpha/beta-methoxy-2-deoxy-D-ribose cyclic carbonates or trimethylene carbonate (TMC), so as to evaluate the Ring-strains of the 2 monomers. Protocol: rwB97XD/6-311+G(2d,p)/cpcm=dichloromethane/T=298.15K Content:- Gaussian09 rev D.01 output files- Ring_Strain_Evaluation.pdf, illustrating the calculations made and summarising the enthalpies computed
R. Jérôme - One of the best experts on this subject based on the ideXlab platform.
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Single-step reactive extrusion of PLLA in a corotating twin-screw extruder promoted by 2-ethylhexanoic acid tin(II) salt and triphenylphosphine
Polymer, 2000Co-Authors: S Jacobsen, Ph Degée, Ph Dubois, H. G. Fritz, R. JérômeAbstract:The Ring Opening Polymerisation of L,L-lactide using an equimolar complex of 2-ethylhexanoic acid tin(II) salt Sn(Oct)2 and triphenylphosphine P(φ)3 as catalyst shows for the first time a reactivity providing a Polymerisation propagation rate fast enough to imagine a continuous single- step reactive extrusion process for bulk Polymerisation. The Ring Opening Polymerisation has been realised on a corotating closely intermeshing twin- screw extruder, using a specially designed screw concept to provide sufficient energy input and mixing for further enhancement of the propagation rate, without detrimentally enhancing dePolymerisation or transesterification reactions. Using one chosen screw and processing concept on a twin-screw extruder with 25 mm diameter and a L/D-ratio of 48, the influence of different processing parameters on the resulting molecular parameters of the Polylactide (PLA) has been determined. Furthermore, the mechanical property profile of the generated PLA-polymers is discussed and related to the molecular parameters.
