Improving the mechanical recycling and reuse of mixed plastics and polymer composites

This is a post-print version of the chapter.In this chapter we will explore the possibilities and viability of commercially recycling and reusing of composites and mixed polymer based waste that is difficult and expensive to separate into individual generic polymers for subsequent recycling. The chapter will also attempt to cover legislations that hinder and drive this technology and give sources of information for further examples of polymer recycling in action

Experimental study of extrusion and surface treatment of organo clay with PET nanocomposites

This article was submitted to and presented at the ANTEC 2008 technical conference.The use of organoclay in polymers is expected to increase annually by about 5 percent. This paper describes melt blending techniques using PET nanocomposites containing commercially available organoclays with different percentage of surfactant coatings. This paper will also evaluate the morphology and mechanical properties of the composites using a range of techniques like, scanning electron microscopy, melt rheology and thermal analysis. Comparisons will be made between properties of amorphous and semi crystalline films in terms of surfactant used and material properties. It will be demonstrated that the quantity of surfactant used with the organoclays can significantly affect dispersion and properties of composites produced.The Thai Government, EU FlexiFunBar Framework 6 Programm

Influences of impurities in recycled plastics on properties of PIM sandwich panels

Powder impression moulding (PIM) is a novel technology for manufacturing lightweight sandwich panels from plastics in powder form. The process is featured by its high tolerant to impurities or contaminants in the feedstock and thus requires much less materials segregation and cleaning operations when use recycled plastics. This paper investigate the influences of polymer impurities and soil contamination on structure and properties of PIM sandwich panels using compositions that simulate a PE-rich recycled plastic feedstock. It is demonstrated that the PIM process can accommodate considerable impurities (rPET residues or soil contamination) in a core dominated by LDPE/HDPE blendes. The variation of flexural properties can be predicted or controlled through monitoring of impurities. There exist significant scopes for reduction of the degree of sorting and cleaning in recycling systems by using lower grades of recyclates and for reduction of the associated costs and energy consumption

PIM moulding of post consumer mixed plastics

Post consumer plastics from household are highly mixed and contaminated and are thus particularly difficult to recycle. Although advances in sorting and cleaning technologies for waste plastics have enable the relatively pure and clean streams such as bottles to be recycled, there is a increasing need for processing technologies that can utilise the low grade and mixed plastic residues from the plastics recovery facilities (PRF). In this work, potentials of utilisation of such feedstock in Powder Impression Moulding (PIM), a process capable of fabricating lightweight sandwich structures, are investigated in terms effects of loading and size of flakes from PE-rich mixed plastics in the formulations of the core on flexural properties of the sandwich panels. It was demonstrated that sandwich panels can be made by incorporating about 75 wt% of coarse flakes of a low-grade mixed plastics material directly obtained from a PRF

Preparation and properties of polypropylene composites reinforced with wheat and flax straw fibres - Part 1: Fibre characterization

Copyright @ 1997 Chapman and Hall. This article is the author version of the published article which can be accessed at the link below.The microstructure, thermal and mechanical properties of flax and wheat straw fibres have been examined with a view to using these natural fibres as reinforcing additives for thermoplastics. In this regard, the fibres were characterized prior to incorporation into the polymer, using a range of techniques, including SEM, image analysis, thermogravimetric analysis and micro-mechanical tensile testing, at room and elevated temperatures. The thermal and mechanical properties obtained have been discussed in relation to the measured composition and structural form of the fibres.This work was supported by the EPSRC, DTI and Cookson Plantpak Ltd through the LINK Crops for Industrial Use programme

Preparation and properties of polypropylene composites reinforced with wheat and flax straw fibres - Part 2: Analysis of composite microstructure and mechanical properties

Copyright @ 1997 Chapman and Hall. This article is the author version of the published article which can be accessed at the link below.The microstructure and mechanical properties of polypropylene composites containing flax and wheat straw fibres are discussed. Particular emphasis has been given to determining the nature and consequences of fibre damage induced during melt-processing operations, fibre orientation occurring in mouldings, and possible interfacial adhesion between the matrix and fibres. Compared to unfilled polypropylene, addition of flax and wheat straw caused a significant increase in tensile modulus, particularly, in the case of flax fibres, which also gave higher tensile yield strength and Charpy toughness, despite a lack of interfacial bonding. Tensile strength was increased further through inclusion of 5% by weight of maleic anhydride-modified polypropylene, which was shown to promote adhesion between fibres and matrix.This work was supported by the EPSRC, DTI and Cookson Plantpak Ltd through the LINK Crops for Industrial Use programme

Experimental study of extrusion and surface treatment of organo clay with PET nano-composites

This article was submitted to and presented at the Polymer Process Engineering 2009 conference.Inclusion of organoclay in engineering polymers is increase annually and this trend will continue for the foreseeable future despite the economic downturn. This paper describes melt blending techniques using PET nanocomposites containing commercially available organoclays with different percentage of surfactant coatings. This paper will also evaluate the morphology and mechanical properties of the composites using a range of techniques like, scanning electron microscopy, melt rheology and thermal analysis. Comparisons will be made between properties of amorphous and semi crystalline films in terms of surfactant used and material properties. It will be demonstrated that the quantity of surfactant used with the organoclays can significantly affect dispersion and properties of composites produced

Environmentally friendly packaging materials from renewable resources as alternatives for oil-based polymers

Nearly 60 m tonnes of waste is produced annually in Europe from “plastic packaging” engendering significant challenges for legislative controls and minimisation of environmental impact. There is an increasing demand for biodegradable packaging, which can be disposed of with minimum environmental impact, but the growing market is still in its infancy predominantly due to a lack of materials having environmental, practical and economic suitability. This research project dealt with some processing challenges of environmentally friendly packaging materials from renewable resources, as a long term solution to mitigate some issues associated with oil based plastic packaging. In this work, novel Polylactic acid (PLA) and starch based composites were developed with the requisite technical properties to fill the gap in the food packaging and cosmetic packaging industry. It was found that starch can be incorporated in a PLA matrix at the 10% level without difficulty in processing in the presence of 2% methyldiphenyl diisocyante. The blend shows properties similar to pure PLA. It was also found that the elongation at break and impact properties of PLA can be increased remarkably by the addition of a biostrength impact modifier. Furthermore, mixing of PLA and starch in the blend is efficient when the PLA particle size is reduced. It was also found that flexible and tougher PLA/starch blend pellets, that can be injection moulded, can be produced by an extrusion process with a range of additives. Each additive has a maximum level that exhibits optimum properties. The blends also established that 15% starch can be incorporated into the PLA matrix to reduce the cost without any processing difficulties. Encouragingly, the presence of an impact modifier in the PLA/starch blends has shown more desirable properties. Furthermore, the mechanical properties of the pellets exposed to increased residence time in the injection moulding barrel and of the test specimens stored for 9 months at 21ºC were also satisfactory for the new blend. The overall results exhibited some attractive properties in the tri blend system, which can be easily adopted by the plastics industry for development of an injection moulded product within the scope of applications such as dry food packaging or cosmetic packaging. A further finding of this project is that biodegradation under a home composting environment can be improved by incorporating starch and certain other modifiers into PLA.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

The Wolfson Centre for Materials Processing Incorporating The Centre for Phosphors and Displays Presented by Dr. K Tarverdi

Established in 1987, the Wolfson Centre has been a focus for materials research in Brunel University. Since its inception, the research in the Centre has been based on the development of extrusion and injection-moulding technologies relating to polymer compound formulation, process-induced structuring, nano-composite processing and the processing of metals, ceramics, soft solids and natural materials. The 'Centre for Phosphors and Display Materials' is a division of the Wolfson Centre for Materials Processing at Brunel University in Uxbridge, West London (only 10 minutes by taxi from London's Heathrow International Airport). It moved into a suit of new and fully re-furbished laboratories in January 2006. The centre was formed 38 years ago and has been continuously researching luminescent materials for this time. We maintain good liaisons with our past researchers and have a network of visiting professors who strengthen and support our expertise. We are a coherent research driven team carrying out novel research into luminescent materials with a particular interest in the displays and lighting industrial sectors. Dr Karnik Tarverdi is Director of Extrusion Technology

Preparation and testing of lanthanum and neodymium with 8-hydroxyquinoline as potential biocide

SIGLEAvailable from British Library Document Supply Centre- DSC:DX174689 / BLDSC - British Library Document Supply CentreGBUnited Kingdo