ISSN:
0032-3888
Keywords:
Chemistry
;
Chemical Engineering
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Ultraoriented films of high density polyethylene (HDPE) have been prepared in continuous lengths by a new method, solid state coextrusion, through conical dies of extrusion draw ratios up to 36. Preformed HDPE billets ∽7 cm long and ∽1 cm in diameter of duPont Alathon 7050R, Mw = 59,000, Mn = 19,900, were split longitudinally into halves and then one or more wafers of the same polymer were inserted between the two sheath halves. Thereafter, the whole assembly was extruded through a conical die of 20° included entrance angle in the absence of lubricant and at temperatures substantially below the melting range yielding continuous and transparent films. The physical and mechanical properties of the HDPE films so produced were evaluated and compared with the properties of the same polymer extruded through a slit die. The high melt transition, tensile modulus and transparency confirm the effectiveness of the new method in continuously attaining ultradrawn films.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pen.760181106
Permalink
