Vannessa Goodship

Management, recycling and reuse of waste composites

Part 1 Management of waste composites: An introduction to composites recycling Legislation for recycling waste composites Waste management. Part 2 Thermal technologies for recycling waste composites: Thermal methods for recycling waste composites Pyrolysis for recycling waste composites Catalytic processing of waste polymer composites Advanced thermal treatment of composite wastes for energy recovery Fluidized bed pyrolysis of waste polymer composites for oil and gas recovery. Part 3 Mechanical technologies for recycling waste composites: Mechanical methods for recycling waste composites Additives to upgrade mechanically recycled plastic composites Improving the mechanical recycling and reuse of mixed plastics and polymer composites Quality and durability of recycled composite materials. Part 4 Improving sustainable manufacture of composites: Clean and environmentally-friendly wet-filament winding Process monitoring and damage detection using optical fibre sensors New developments in producing more functional and sustainable composites. Part 5 Case studies: Designing composite wind turbine blades for disposal, recycling or reuse In-process composite recycling in the aerospace industry Disposal of composite boats and other marine composites Sustainable fibre-reinforced polymer composites in construction Recycling of concrete.

Air-plasma Pre-treatment for Polypropylene Automotive Bumpers

The effect of forced air-plasma pre-treatment, Lectro-treatTM, on polypropylene has been investigated using X-ray photoelectron spectroscopy (XPS), angle-resolved XPS (AR-XPS), and atomic force microscopy (AFM). The pre-treatment process is found to induce both surface chemistry changes and topographical changes. The parameters of the pre-treatment process can be optimised from these observations. The Lectro-treat pre-treatment process has been used for adhesive bonding of a demonstrator component: a bumper assembly. The adhesively bonded bumpers performed successfully in standard automotive tests.

Interfacial instabilities in multimaterial co-injection mouldings : Part 1 - Background and initial experiments

Abstract Interfacial adhesion between the skin and core is vital for successful co-injection moulding. This is the first paper in a series, which introduces and describes an in mould method of mixing that is applicable regardless of the compatibility of the materials. It works by inducing turbulent mixing at the interface between the skin and core materials. It makes use of the change that occurs from laminar to turbulent flow at high injection speeds in co-injection moulding. This novel approach takes advantage of the moulding parameters already available within the co-injection system to offer an expanded range of material combinations for multimaterial moulding. Comparisons are made between multimaterial mouldings made with miscible polymers, immiscible polymers with no compatibiliser, and immiscible polymers bonded by compatibilisers.

In-mould painting by spraying thermoset powder coating into a closed mould, followed by standard thermoplastic injection moulding : part 1 : introducing the in-spire process

Injection moulding technologies are constantly evolving to meet changing customer requirements, improved cost effectiveness and to meet new environmental legislation. One such technology is in-mould decoration (IMD). This technique is attractive due to increased customer desire for multi-functional and decorative products and includes any process in which a fully, or partially, decorated component is produced directly from the moulding process. A new patented IMD process has been developed to produce a painted component direct from the injection moulding tool. It uses thermoset powder coatings which are sprayed under pressure through a valve into a closed mould using a novel feed system. The heat of the tool softens the coatings which are then cured by the injection of thermoplastic polymer into a standard injection moulding system. In this first paper initial design features and considerations as well as the process itself are discussed.

Interfacial instabilities in multimaterial co-injection mouldings: Part 2 - Interfacial mixing in transparent mouldings

Abstract Previous research in co-injection moulding has produced viscosity ratio guidelines for skin and core components, which must be followed if good core distribution is to be achieved. However, by examining two phase systems of PMMA-PC, which fall within the recommended viscosity range, this work shows that viscosity matching of materials is not a sufficient requirement for interfacial stability. The transparency of the materials allows areas of interfacial mixing to show up as streaks in the mouldings, so that factors affecting stability can be determined. One system is found to be more stable than the others. Explanations for such effects are given by consideration of interfacial mixing, viscosity, tooling geometry, injection speeds, interfacial stresses and shear in multilayered mouldings.

In mould painting using thermoset powder coating and thermoplastic substrate in closed tool injection moulding

Abstract In mould decoration (IMD) is attractive because a fully, or partially, decorated component is produced directly from the moulding process, with reduced emissions at lower process costs when compared to traditional techniques. A new IMD process has been developed to produce a painted component direct from the injection moulding tool. This incorporates the pressure spraying of thermoset powders through a valve into a closed mould. The residual heat of the tool initially softens the thermoset. The high temperature of thermoplastic polymer injected in a standard injection moulding subsequently cures the thermoset. The resultant product combines both thermoplastic and thermoset in a single injection moulding cycle. This paper presents frames from high speed video capture of powder mould filling and the results of INSPIRE (in mould spray painting, impact reduced on the environment) initial injection moulding using thermoset polyester and acrylonitrile butadiene styrene (ABS). The parameters that affect material distribution are examined and discussed. Similarities to the coinjection moulding process are noted.

Removing the paint shop process: options for painting and decorating injection mouldings

Technological drivers exist for the complete removal of the painting process. These include satisfying changing customer requirements for multi-functional and decorative products, improved cost effectiveness and to meet stringent environmental legislation; for example in lower emissions requirements and recycling/disposal. Alternatives to the painting process are discussed. One such technology is In-Mould Decoration (IMD). This technique is attractive because a fully, or partially, decorated component is produced directly from the moulding process, with reduced emissions at lower process costs when compared to traditional techniques. A new IMD technique called IN SPIRE and its potential for energy savings compared to a paint shop is considered.

Microcellular foaming with supercritical CO2 in injection moulding

This paper discusses the systems for microcellular injection moulding developed and patented by Trexel and IKV. It then introduces a third design with initial findings and recommendations for modifications. The results suggest that microcellular foaming is possible introducing supercritical carbon dioxide in the nozzle providing certain design criteria are met such as a sufficient pressure drop from the plastication unit to the mould to enable rapid nucleation. Results from experiments with polystyrene are presented with consideration for pressure drop, weight reduction and injection speed.

Digital Printing of Titanium Dioxide for Dye Sensitized Solar Cells

Silicon solar cell manufacturing is an expensive and high energy consuming process. In contrast, dye sensitized solar cell production is less environmentally damaging with lower processing temperatures presenting a viable and low cost alternative to conventional production. This paper further enhances these environmental credentials by evaluating the digital printing and therefore additive production route for these cells. This is achieved here by investigating the formation and performance of a metal oxide photoelectrode using nanoparticle sized titanium dioxide. An ink-jettable material was formulated, characterized and printed with a piezoelectric inkjet head to produce a 2.6 µm thick layer. The resultant printed layer was fabricated into a functioning cell with an active area of 0.25 cm2 and a power conversion efficiency of 3.5%. The binder-free formulation resulted in a reduced processing temperature of 250 °C, compatible with flexible polyamide substrates which are stable up to temperatures of 350 ˚C. The authors are continuing to develop this process route by investigating inkjet printing of other layers within dye sensitized solar cells.

Recycling issues in polymer matrix composites

- Introduction - The problems of reuse in polymer composites - Plastic waste disposal into other materials - Mechanical recycling of polymeric matrix composites - Recovery techniques - Properties of recovered fibres - Future strategies for making polymer matrix composites more recyclable - Conclusions - Sources of further information and advice - References - Appendix: abbreviations