A series of ultra-high-molecular-weight reactor powders with different technological prehistory were utilized for obtaining fibers through the gel technology. The fibers prepared from some powders exhibited high draw ratios and good mechanical properties (Young's modulus and tensile stress) but other powders yielded fibers of very low drawability. The low-frequency Raman study revealed that the straight-chain-segment (SCS) length distributions in dried gels prepared from powders of "drawable" group are bimodal, while the gels issued from powders unsuitable for fiber drawing have unimodal length distributions of SCS. (C) 2007 Wiley Periodicals, Inc.