abstract |
The invention relates to a process for producing gel-spun ultra high molecular weight polyethylene (UHMWPE) fibres having high tensile strengths and improved creep rates wherein the UHMWPE used in said process is characterized by a difference in the phase angle according to Formula (1) Δδ = δ0.001 - δ100 of at most 42°, wherein δ0.001 is the phase angle at an angular frequency of 0.001 rad/sec; and δ100 is the phase angle at an angular frequency of 100 rad/sec as measured with a frequency sweep dynamic rheological technique at 150°C on a 10% solution of UHMWPE in paraffin oil, provided that δ100 is at most 18°. The invention further relates to gel-spun UHMWPE fibres produced thereof. The gel-spun UHMWPE fibres of the invention have a tensile strength of at least 4 GPa, and a creep rate of at most 5 x 10-7 sec-1 as measured at 70°C under a load of 600 MPa. The gel-spun UHMWPE fibres produced thereof are useful in a variety of applications, the invention relating in particular to ropes, medical devices, composite articles and ballistic-resistant articles containing said UHMWPE fibres. |