Production of PVAc–starch composite materials by co-grinding — Influence of the amylopectin to amylose ratio on the properties

Nadine Le Bolay (1) , Sonia Molina-Boisseau (2, 3)

1 LGC - Laboratoire de Génie Chimique
2 CERMAV - Centre de Recherches sur les Macromolécules Végétales
3 ICMG - Institut de Chimie Moléculaire de Grenoble

Mixtures of polyvinyl acetate (PVAc) filled with two starch types containing different amylopectin to amylose ratios were co-ground in a laboratory tumbling ball mill. The influence of the starch nature and of the co-grinding treatment on the production mechanism and on the composite properties was studied. The thermal and mechanical properties were characterized, as well as the behavior in water. The presence of starch in the mixture reduces agglomeration phenomena between matrix particles, as well as the mobility of polymeric chains. While a simple mixing of the constituents generates starch concentration points in the matrix, co-grinding favors filler dispersion and PVAc–starch interactions enabling an increase of the mixture properties without adding any chemical agent. The amylopectin to amylose ratio does not affect significantly mechanical properties while a high amylopectin rate promotes water uptake.

Mots clés: Co-grinding; Composite materials; Starch; Amylopectin to amylose ratio; Properties

Domaines: Génie chimique; Génie des procédés

Nadine Le Bolay, Sonia Molina-Boisseau. Production of PVAc–starch composite materials by co-grinding — Influence of the amylopectin to amylose ratio on the properties. Powder Technology, 2014, 255, pp.36-43. ⟨10.1016/j.powtec.2013.10.050⟩. ⟨hal-01894061⟩