POS9-0165
Marine-Biodegradable Oligo(L-lactide) as a Plasticizer for Enhancing the Properties of Cellulose Acetate
Topic
S9. Polymer Technology for Sustainability
When and Where
Oct 1, 2026
08:30 - 09:30
Room 301 (Grand Ballroom)
Session Chairs
Jinkee HONG
Ki Su KIM
Presenter(s)
Jin Ho Seok (University of Tokyo)
Co-Author(s)
Abstract
Cellulose acetate (CeAc) is a widely used biomass-based material. At low degree of substitution (DS < 2.5), CeAc exhibits marine biodegradability while retaining high transparency and strength, but it is brittle and requires high molding temperatures (210–240 °C). Conventional plasticizers such as phthalates can leach during degradation, creating environmental and health concerns, so marine-biodegradable plasticizers are needed. This study evaluates oligo(L-lactide) (OLA) and terminally acylated OLA as plasticizers for CeAc with DS = 2.2 (CeAc2.2). OLA with degrees of polymerization (DP) of 20 to 100 was synthesized by ring-opening polymerization; thermal decomposition temperature (Td), glass transition temperature (Tg), and crystallinity all increased with DP. BOD tests confirmed marine biodegradability. Terminal acylation raised thermal stability, enabling melt blending with CeAc2.2. Acetyl- and hexanoyl-modified oligomers retained biodegradability, whereas benzoyl modification suppressed it. Blends of CeAc2.2 with OLA (0.25 to 10 wt%) were compatible, yielding transparent, glossy films. Short-chain OLA (DP 20) increased tensile strength and markedly raised elongation at break, imparting toughness, whereas DP 100 oligomers gave different tendancy of improvement. DMA showed a single Tg that decreased with oligomer content, indicating miscibility. Acyl-modified OLA improved mechanical properties and thermal moldability at 10 wt%. These results show that marine-biodegradable OLA plasticizes low DS CeAc, and that terminal acylation with non-aromatic ester groups enhances thermal stability without compromising biodegradability.
