Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE This study systematically elucidates the multi-scale mechanisms through which wet granulation, as an innovative pretreatment approach, influences the properties of glass fiber-reinforced PTFE composites. Through comparison with the conventional dry-mixing process, the underlying mechanism by which wet granulation synergistically optimizes fiber dispersion, interfacial bonding, and matrix structure to substantially enhance the overall composite performance is revealed.

ABSTRACT
Glass fiber (GF) reinforcement is widely employed to enhance the mechanical and tribological properties of PTFE. However, conventional dry-mixing processes are inadequate for resolving the dual challenges of nonuniform fiber dispersion and weak interfacial bonding. This work pioneers the application of wet granulation in the fabrication of PTFE/GF composites, demonstrating that this process induces fibrillated PTFE structures on GF surfaces while simultaneously achieving three-dimensional uniform fiber dispersion within the matrix. Experimental results reveal that the W-PTFE/GF composite prepared via wet granulation exhibits markedly superior properties compared to its conventionally dry-mixed counterpart: tensile strength increases from 17.8 to 20.8 MPa, compressive modulus rises from 857 to 899 MPa, and 24-h creep strain decreases from 4.4% to 3.7%. Most notably, under dry friction conditions, the W-PTFE/GF composite achieves an exceptionally low wear rate of 6.09 × 10−6 mm3/(N·m), exhibiting the most stable friction coefficient among all tested samples. For the first time, this study proposes a multi-scale synergistic enhancement mechanism integrating “uniform dispersion, interfacial strengthening, and matrix optimization,” elucidating the intrinsic mechanism by which wet granulation enables multi-scale structural control through interfacial fibrillation. It provides a novel processing route and theoretical foundation for the industrial fabrication of high-performance, long-life PTFE-based composite products.