Sustainable Biopolymer Colloids: Advances in Morphology for Enhanced Functionalities

Biobased polymers such as cellulose, chitin/chitosan, starch, alginate, and lignin are making inroads as sustainable, environmentally safe and biodegradable alternatives to synthetic colloidal materials. This perspective summarizes recent developments in preparation techniques, identifies critical barriers, and proposes future directions for improving the performance and applicability of biopolymer colloidal structures. A major focus is the sustainable colloids morphology as a means of introducing functionality without chemical modification. We discuss the strategies for fabrication of four distinct classes of colloidal morphologies from biobased materials: spherical and nonspherical particles, fibers/fibrils, and films. Their preparation methods can be categorized into physical and chemical approaches. Despite advancements in these methods, challenges persist regarding uniformity, scalability, desired properties, and the need to enhance environmental sustainability. Addressing these challenges is essential for facilitating the transition from synthetic polymers to greener, more sustainable, and microplastic-free colloidal alternatives.