How to distinguish between cross-linked PPS and linear PPS, and what are their differences?

PPS can be divided into two major categories. One is PPSbased on cross-linked polymers, which undergoes heat treatment in the presence of air. The polymer forms a cross-linked three-dimensional network structure through oxygen as a medium, thus maintaining high rigidity and wear resistance, low creep and stress relaxation characteristics at high temperatures. Additionally, heat-treated cross-linked PPS materials usually exhibit a dark brown color. 

The other is based on linear polymers. Linear PPS is the second generation of PPS products, which is manufactured without heat treatment. Its molecular structure is straight-chain, resulting in relatively low rigidity but good toughness, impact resistance, and tensile strength; slow cooling and curing rates; excellent fluidity, suitable for thin-walled product molding, and high weld seam strength; low ionic impurities, making it suitable for demanding electronic fields and fuel cell components; furthermore, due to its high purity, linear PPS has lower moisture absorption than cross-linked PPS, smaller dimensional changes, and better electrical insulation properties; unheat-treated linear PPS is light yellow with high whiteness and can be dyed.