Preparation of microcapsules from complex coacervation of Gantrez-gelatin. I. Development of the technique

Trials to induce complex coacervation between two grades Gantrez-AN polymer (G-AN), and Type A gelatin were made. Physical parameters influencing the coacervation process were studied. Maximum coacervation was attained when the pH of the gelatin solution was at 6.8. Increasing the molecular weight of Gantrez decreased the ratio of combination of both polymers. The ratio for optimum coacervation was 1:4 for Gantrez-AN 119-gelatin system and 2:3 for Gantrez-AN 149-gelatin system with total colloid concentration of 2.5 g per cent w/v in both cases. High stirring speed gave almost spherical uniform coacervates. Recovery of the product as water-insoluble discrete units required the use of formaldehyde and isopropanol for coacervate denaturation and flocculation, respectively.