Effect of processing parameters on the morphology development during extrusion of polyethylene tape: An in-line small-angle X-ray scattering (SAXS) study

POLYMER

卷:54

Article

Heeley, E. L.¹  Gough, T.²  Hughes, D. J.³  Bras, W.⁴  Rieger, J.⁵  Ryan, A. J.⁶ 

[1] Open Univ, Dept Phys Sci, Milton Keynes MK7 6AA, Bucks, England

[2] Univ Bradford, Sch Engn Design & Technol, Bradford BD7 1DP, W Yorkshire, England

[3] Univ Warwick, WMG, Coventry CV4 7AL, W Midlands, England

[4] Netherlands Org Sci Res NWO, DUBBLE CRG ESRF, F-38043 Grenoble, France

[5] BASF SE, Polymer Phys, D-67056 Ludwigshafen, Germany

[6] Univ Sheffield, Ctr Polymer, Dept Chem, Sheffield S3 7HF, S Yorkshire, England

关键词: Polymer extrusion;    Low density polyethylene (LDPE);    Small-angle X-ray scattering (SAXS);   

DOI  :  10.1016/j.polymer.2013.10.004

来源: Elsevier

【 摘 要 】

The in-line development of crystalline morphology and orientation during melt extrusion of low density polyethylene (LDPE) tape at nil and low haul-off speeds has been investigated using Small-Angle X-Ray Scattering (SAXS). The processing parameters, namely haul-off speed and distance down the tape-line have been varied and the resulting crystalline morphology is described from detailed analysis of the SAXS data. Increasing haul-off speed increased orientation in the polymer tape and the resulting morphology could be described in terms of regular lamellar stacking perpendicular to the elongation direction. In contrast, under nil haul-off conditions the tape still showed some orientation down the tape-line, but a shish-kebab structure prevails. The final lamellae thickness (similar to 50 angstrom) and bulk crystallinity (similar to 20%), were low at, for all processing conditions investigated, which is attributed to the significant short-chain branching in the polymer acting as point defects limiting lamellae crystal growth. (C) 2013 Elsevier Ltd. All rights reserved.

【 授权许可】

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