Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE Co-rotating twin-screw extrusion (~120°C) of corn starch and lignin in a choline chloride/monoethanolamine (ChCl:MEA) deep eutectic solvent (DES) generates a DES-bridged starch–lignin interphase, enabling simultaneous starch plasticization and interfacial compatibilization.

ABSTRACT
The influence of the choline chloride:monoethanolamine (ChCl:MEA) deep eutectic solvent (DES) ratio (1:2–1:5) on corn-starch/lignin blends processed by twin-screw extrusion is systematically mapped. With increasing MEA content, coherent composition-dependent responses are obtained: tensile strength (σ

t
) is reduced while elongation at break (ε

b
) is increased; stabilized torque is reduced and melt flow index (MFI) is increased; the glass transition temperature (T

g
) and water contact angle are decreased. Ratio-dependent red-shifts and attenuation in the O–H/N–H region are observed by FTIR, together with losses in aromatic and carbonyl bands, consistent with DES–polymer hydrogen bonding and partial lignin solvation. Reduced short-range order and mid-range crystallinity are indicated by XRD. To prioritize deployability, a multi-criteria decision screen is applied (targets: σ

t
 ≥ 1.0 MPa; MFI 3–5 g/10 min; T

g
 ≤ 60°C; contact angle 50°–75°; CrI 15%–30%). A ChCl:MEA ratio of 1:4 is uniquely identified as satisfying all targets simultaneously (σ

t
: 1.09 MPa, ε

b
: 197%, MFI: 3.68 g/10 min, T

g
 ≈ 40°C, contact angle ≈52°, CrI ≈ 22%), whereas 1:5 is over-plasticized. Ratio tuning of ChCl:MEA is thus established as a single-parameter, green approach for matching flexibility, processability, and surface activity, yielding a practical operating point for film/sheet bioplastics.