Dynamic mechanical thermal analysis transitions of partially and fully substituted cellulose fatty esters

Carlos Vaca-Garcia (1) , Giuseppe Gozzelino (2) , Wolfgang Glasser (3) , Marie-Elisabeth Borredon (1)

1 CAI - Chimie Agro-Industrielle
2 Polito - Politecnico di Torino = Polytechnic of Turin
3 Virginia Polytechnic Institute and State University [Blacksburg]

The main transitions of cellulose fatty esters with different degrees of substitution (DSs) were investigated with dynamic mechanical thermal analysis. Two distinct main relaxations were observed in partially substituted cellulose esters (PSCEs). They were attributed to the glass‐transition temperature and to the chain local motion of the aliphatic substituents. The temperatures of both transitions decreased when DS or the number of carbon atoms (n) of the acyl substituent increased. Conversely, all the transitions of fully substituted cellulose esters occurred within a narrow temperature range, and they did not vary significantly with n. This phenomenon was explained by the formation of a crystalline phase of the fatty substituents. The presence of few residual OH groups in PSCEs was responsible for a large increase in the storage bending modulus, and it eliminated the effect of n on damping.

Mots clés: Cellulose fatty esters; Dynamic mechanical thermal analysis (DMTA); Thermal mechanical analysis (TMA); Glass transition; Damping; Fox equation; Biopolymers; Structure‐property relations

Domaines: Polymères

Carlos Vaca-Garcia, Giuseppe Gozzelino, Wolfgang Glasser, Marie-Elisabeth Borredon. Dynamic mechanical thermal analysis transitions of partially and fully substituted cellulose fatty esters. Journal of Polymer Science Part B: Polymer Physics, 2002, 41 (3), pp.281-288. ⟨10.1002/polb.10378⟩. ⟨hal-02079769⟩