3,986 research outputs found
Recycling of fiber reinforced thermosetting composites
No full textThe recycling process for production and end-of-life fiber reinforced thermoset plastic waste is usually a two-step process: the reclamation of the fibers from the matrix through its degradation and their recovery and remanufacture into new feedstock material or product. The chapter will be opened by an outlook of the current sources of waste in the composite industry. This will comprise a review of the principal fiber reclamation technologies, categorizing them based on the degradation mechanism (pyrolysis or solvolysis), and an overview of the obtainable properties will be provided. The chapter will then focus on the description of the available remanufacturing technologies for reclaimed carbon fibers, into new recycled composite materials. The chapter will also provide an overview of the current industrial landscape
Film International Issue 1
No full textContents: Editorial (Michael Tapper), Ingmar Bergman's Writings and Films (Maaret Koskinen), The Perfect Money Machine(s): George Lucas and Steven Spielberg (Jon Lewis), Genre Films and Cultural Myth (Barry Keith Grant), Nobody's Perfect: Billy Wilder and Postwar American Cinema (William Rothman), Peter Watkins: Culloden x 2 (Nicholas J Cull/John R Cook). Reviews: books, films
Film International Issue 1
No full textContents: Editorial (Michael Tapper), Ingmar Bergman's Writings and Films (Maaret Koskinen), The Perfect Money Machine(s): George Lucas and Steven Spielberg (Jon Lewis), Genre Films and Cultural Myth (Barry Keith Grant), Nobody's Perfect: Billy Wilder and Postwar American Cinema (William Rothman), Peter Watkins: Culloden x 2 (Nicholas J Cull/John R Cook). Reviews: books, films
Mapping a gene for rheumatoid arthritis on chromosome 18q21
No full textAlthough single chi-square analysis of the North American Rheumatoid Arthritis Consortium (NARAC) data identifies many single-nucleotide polymorphisms (SNPs) with p-values less than 0.05, none remain significant after Bonferroni correction. In contrast, CHROMSCAN evades heavy Bonferroni correction and auto-correlation between SNPs by using composite likelihood to model association across all markers in a region and permutation to assess significance. Analysis by CHROMSCAN identifies a 36-kb interval that includes the most significant SNP (msSNP) observed in a 10-Mb target suggested by linkage. Unexpectedly, stratification by gender and age of onset shows that association evidence comes almost entirely from females with age of onset less than 40. Combining evidence from a meta-analysis of linkage studies and three subsets of the NARAC data provides significant evidence for a determinant of rheumatoid arthritis in a 36-kb interval and illustrates the principle that estimates of location and its information are more powerful than estimates of p-values alone
Exclusive electroproduction of rho0 and J / psi mesons at HERA
No full textExclusive production of rho(0) and J/psi mesons in e(+)p collisions has been studied with the ZEUS detector in the kinematic range 0.25 < Q(2) < 50 GeV2, 20 < W < 167 GeV for the rho(0) data and 2 < Q(2) < 40 GeV2, 50 < IS' < 150 GeV for the J/psi data. Cross sections for exclusive rho(0) and J/psi, production have been measured as a function of Q2, W and t. The spin-density matrix elements r(00)(04), r(1-1)(1) and Rer(10)(5) have been determined for exclusive rho(0) production as well as r(00)(04) and r(1-1)(04) for exclusive J/psi production. The results are discussed in the context of theoretical models invoking soft and hard phenomena
A closed-loop recycling process for discontinuous carbon fibre polyamide 6 composites
No full textThe effects of a closed-loop recycling methodology are evaluated for degradation using a discontinuous carbon fibre polyamide 6 (CFPA6) composite material. The process comprises two fundamental steps: reclamation and remanufacture. The material properties are analysed over two recycling loops, and CFPA6 specimens show a total decrease of 39.7% (±3.5) in tensile stiffness and 40.4% (±6.1) in tensile strength. The results of polymer characterisation and fibre analysis suggested that the stiffness reduction was likely due to fibre misalignments primarily caused by fibre agglomerations, as a result of incomplete fibre separation, and by fibre breakages from high compaction pressures. The ultimate tensile strain was statistically invariable as a function of recycling loop which indicated minimal variation in polymer structure as a function of recycling loop. To the authors’ best knowledge, the mechanical performance of the virgin CFPA6 is the highest observed for any aligned discontinuous carbon fibre thermoplastic composites in the literature. This is also true for recycled specimens, which are the highest observed for any recycled thermoplastic composite, and, for any recycled discontinuous carbon fibre composite with either thermosetting or thermoplastic matrices
Development of a closed-loop recycling process for highly aligned discontinuous carbon fibre thermoplastic composites
No full textIn this study the effects of a closed-loop recycling methodology are evaluated for degradation using thermoplastic ocmposites based on discontinuous fibres. The process comprises two fundamental steps: reclamation and remanufacture. The material properties are analysed over two recycling loops. Carbon fibre reinforced polypropylene (CFPP) specimens show no decrease in mechanical properties over repeated recycling loops, the final specimens show an increase of 26 % and 43 % in ultimate tensile strength and ultimate strain, respectively. These are attributed to cumulative matrix residue on the fibre surface after reclamation and subsequently increased fibre-matrix adhesion. The improvement of CFPP properties validate the potential of this proof-of-concept, closed-loop recyclable material. Future studies will investigate alternative, higher performance matrices
An evaluation of life cycle assessment and its application to the closed-loop recycling of carbon fibre reinforced polymers
No full textLife cycle assessment (LCA) is a valuable tool for establishing the environmental burdens of a composite material over its lifetime. It is therefore of importance to the composites industry as a material selection tool when determining the applicability of recycled composites in the component design phase. This review paper evaluates the LCA framework and its ability to accurately determine the benefits of closed-loop composite recycling, with the aim of aiding future material selection for recycled CFRP. LCA is a powerful tool for CFRP assessment when used in combination with an economic and technical component as covered by the integrated Life Cycle Engineering approach. The broad range of values available in LCA databases may prove an issue for cross comparison between studies and provide disparate results leading to impractical conclusions. The use phase offers the greatest potential for CFRP emissions savings in the transport sector; the advent of closed-loop recycling for CFRP may provide the multiple use phases required to breakeven on the significant energy burden of production or possibly provide net environmental savings gains over traditional materials
Development of a closed-loop recycling process for discontinuous carbon fibre polypropylene composites
No full textIn this study the effects of a closed-loop recycling methodology are evaluated for degradation using a discontinuous carbon fibre polypropylene (CFPP) composite material. The process comprises two fundamental steps, reclamation and remanufacture. The material properties are analysed over two recycling loops. For neat polypropylene, the molecular weight analysis indicates evidence of minimal matrix degradation that does not affect the material behaviour, as demonstrated by the shear tests. CFPP specimens show no decrease in mechanical properties over repeated loops, the final specimens show an increase of 26% and 43% in ultimate tensile strength and ultimate strain, respectively. These are attributed to cumulative matrix residue on the fibre surface after reclamation and subsequently increased fibre-matrix adhesion. The improvement of CFPP properties and insignificant variability in the tensile properties and molecular weight distribution of neat polypropylene validate the potential of this proof-of-concept, closed-loop recyclable material. Future studies will investigate alternative, higher performance matrices
Devleopment of a closed-loop recycling process for short carbon fibre composites: Matrix
No full textIn this study, the degradation effects of multiple closed-loop recycling processes evaluated for polypropylene. This is the first in a series of studies that aim to develop a fully recyclable composite material based on aligned discontinuous carbon fibre. Mechanical and material property fluctuations are analysed after three iterations. Molecular weight analysis indicates slight degradation in chain length; however, this is not reflected in material or mechanical performance. The limited variability of the tensile properties and the molecular weight distribution after multiple recycling iterations is insignificant and therefore promising for further development of the recyclable composite material by introducing fibres
- …
