Polymer science crystallisation

Abstract The morphology of polyethylene has been an important theme in polymer science for more than 50 years. This review provides an historical background and presents the important findings on five specialised topics the crystal thickness, the nature of the fold surface, the lateral habit of the crystals, how the spherulite develops from the crystal lamellae, and multi-component crystallisation and segregation of low molar mass and branched species. 

Polymers are widely used in nature to regulate many processes involving materials growth, such as the development of bone tissue and the production of shells by sea-creatures. The design of synthetic polymers to control processes such as crystallisation and deposition of (in)organic materials is known as biomimetics, and is a rapidly expanding area of polymer science. 

Rg. 5.9 A transmission electron micrograph of a replica of a fracture surface of extended-chain polychlorotrifluoro-ethylene. The sample was crystallised under 100 MPa pressure at 250°C for 16 h. The sample was first heated above 295°C. After crystallisation it was cooled rapidly to room temperature, followed by release of the pressure. (Reproduced by permission of the Society of Polymer Science, Japan.)... 

Figure 2.7 Crystallisation behaviour of PEO/phenolic blends with varying concentration of phenolic resin. Reproduced with permission from D. Ratna, T. Abraham and K. Kocsis, Journal of Applied Polymer Science, 2008, 108, 2156 2008, John Wiley and Sons Publishers...

Long, Y., Shanks, R.A. and Stachurski, Z.H. (1995), A Practical Guide to Study Kinetics of Polymer Crystallisation, Progress in Polymer Science, 20, 651-701. 

Andrew Keller (1925-1999) who in 1957 found that the polymer polyethylene, in unbranched form, could be crystallised from solution, and at once recognised that the length of the average polymer molecule was much greater than the observed crystal thickness. He concluded that the polymer chains must fold back upon themselves, and because others refused to accept this plain necessity, Keller unwittingly launched one of the most bitter battles in the history of materials science. This is further treated in Chapter 8, Section 8.4.2. 

ACS, Polymeric Materials Science Engineering Fall Meeting 1999. Volume 81. Conference proceedings. New Orleans, La., 22nd-26th Aug. 1999, p.236-7 CRYSTALLISATION AND MELTING OF POLYMER CRYSTALS REVEALED BY T-M DSC Toda A Oda T Tomita C Hikosaka M Arita T Samyama Y... 

P. J. Philips, Polymer Morphology and Crystallisation) Materials Science and Technology 19,1153-1160 (2003). 

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