Swelling of PVC particles during gelation and fusion of plastisols as observed with small-angle light scattering

Small-angle light scattering was employed as a nondestructive technique for the in situ observation of swelling of PVC particles during gelation and fusion. One typical plastisol grade of PVC and three different plasticizers were used. The results demonstrate that quantitative measurements of average PVC particle size appear possible while they are in the process of swelling with plasticizers. From the degree of swelling the solvent power of plasticizers may be evaluated. The ranking of plasticizers made in this manner was in good agreement with the previous studies involving viscoelastic measurements.