There is provided a hollow fiber membrane for vacuum membrane distillation having a maximum tensile strength of a ≥3.5 MPa and a liquid entry pressure (LEP) of ≥3.0 bar, wherein the hollow fiber membrane is a single layer hollow fiber membrane comprising a wall with a thickness of ≤150 μm and a cross-section comprising two open cell layers with an array of interconnected pores and a macrovoid layer between the two open cell layers. The hollow fiber has improved mechanical strength and vacuum membrane distillation flux.