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General rightsThis document is made available in accordance with publisher policies. Please cite only the published version using the reference above. Full terms of use are available: http://www.bristol.ac.uk/pure/about/ebr-terms Hamerton, E-mail: ian.hamerton@bristol.ac.uk This review is respectfully and affectionately dedicated to Dr Horst D Stenzenberger, who has been an inspirational figure in modern BMI chemistry, always happy to share his extensive knowledge of this field. ABSTRACT:The chemistry of bismaleimides (BMIs), their blends and copolymers is reviewed critically with particular emphasis placed on the development of the field after 1990, which was marked by several comprehensive review articles. A general introduction to the structure property relationships of BMIs is presented, outlining the development of the preparative chemistry, and the early strategies adopted to address the inherent brittleness of the cured 'first generation' BMI polymers. 'Second generation', diallylbisphenol-toughened BMIs, form the basis of the benchmark commercial systems, and the polymerization mechanism is discussed. The current review is placed in context, addressing the issues of cost, processing and precursor toxicity, the major barriers to wider acceptance of BMIs. The main body of the review evaluates a number of observations made by Dr Horst Stenzenberger in 1990, for the future development of BMI technology. Hence, the synthesis of novel bismaleimide building blocks, incorporation of new thermoplastics and additives, and blending with new thermosetting comonomers are all discussed in detail. The aforementioned review had been written before the concept of nanocomposites or shape memory polymers had been explored with BMIs, but the fields have since grown (especially in the case of the former topic) and are reviewed herein. The application of BMIs to continuous fibre composites is one of the proposed fields of commercial development. The topic falls a little beyond the scope of the present review of BMI chemistry, and is the subject of another publication, but a brief discussion of the most recent developments is presented. The review is concluded with some thoughts about the future outlook for BMI chemistry.

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The hand layup of pre-impregnated woven materials is still a large part of the composite manufacturing industry, requiring the skills and experience of a human workforce to form flat plies into complex shapes. It is capable of producing high performance and complex parts, but can be an expensive and variable process. Despite its importance, there appears to have been very little research into the actual methods and techniques used by workers to manipulate flat sheets of composite material into shape during layup. This work presents the first known detailed study of the approach and techniques used by laminators. Four participants laid up onto 15 different shaped molds that replicated features commonly found on composite components. The actions used in layupwere grouped into eight distinct techniques. Use of these techniques across tasks of different geometry, ramp angles, radii and drape path was identified using video analysis techniques from the ergonomics field. This revealed strong links between specific features and techniques, revealing a systematic approach to layup. This has enabled the first step toward producing a design for manufacture knowledge base surrounding hand layup. This could then be used to inform the development of the layup process, improve training methods and assist in the design of future automated solutions.