PGS with a high degree of functional group conversion (pCOOH = 71%) but still in a un cross-linked form was obtained in a very short time (115 min) compared to the process carried out as commonly in literature (pCOOH = 66%, 24 h). Moreover, the cross-linked material was obtained if the reaction time was slightly longer than the optimal 115 min. So, in this study synthesis was shortened from 24 h (literature) to 115 min and the obtained polyester could be very fast cross-linked to insoluble form. It is a huge advantage when considering industrial production. Currently, published syntheses are often noneconomical and nonecological due to long processing time in high temperatures. This work brings PGS closer to becoming a competitive material for PLA, PCL or similar materials, not only in the scientific field but also industrial. Of course, studying the cross-linking procedure of produced prepolymer in the future is necessary. What is very important is that statements based on polymerization theories from previous work are also true for the case in this study. Catalyst and water removal did not affect the value of the gelling point. It is very significant for designing or optimizing new processes for prepolymer synthesis.