The influence of silane surface modification on microcrystalline cellulose characteristics

Roberta Motta Neves; Heitor Luiz Ornaghi Jr; Ademir José Zattera; Sandro Campos Amico

doi:10.1016/j.carbpol.2019.115595

The influence of silane surface modification on microcrystalline cellulose characteristics

Carbohydr Polym. 2020 Feb 15:230:115595. doi: 10.1016/j.carbpol.2019.115595. Epub 2019 Nov 11.

Authors

Roberta Motta Neves¹, Heitor Luiz Ornaghi Jr², Ademir José Zattera³, Sandro Campos Amico⁴

Affiliations

¹ Postgraduate Program in Mining, Metallurgical and Materials Engineering (PPGE3M), Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves, 9500, Porto Alegre, RS 91501-970, Brazil. Electronic address: robertamneves@gmail.com.
² Fatigue and Aeronautical Material Research Group, Department of Materials and Technology, São Paulo State University (UNESP), School of Engineering, 12516-410. Guaratinguetá, SP, Brazil.
³ Postgraduate Program in Engineering of Processes and Technologies (PGEPROTEC), Universidade de Caxias do Sul (UCS), Rua Francisco Getúlio Vargas, 1130, Caxias do Sul, RS 95070-560, Brazil.
⁴ Postgraduate Program in Mining, Metallurgical and Materials Engineering (PPGE3M), Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves, 9500, Porto Alegre, RS 91501-970, Brazil.

PMID: 31887881
DOI: 10.1016/j.carbpol.2019.115595

Abstract

Microcrystalline cellulose (MCC) can be a reinforcement in composites, especially after surface modification. In this paper, MCC was modified using 3-aminopropyltriethoxysilane (APTES) in the following ratios (MCC/APTES): 1:3, 1:4, 1:5, 1:10). The MCC morphologies did not change with the treatment even though the distribution of APTES over the MCC surface varied. FTIR analysis showed MCC and APTES characteristic peaks for all samples. The crystallinity index (CI) decreased with the APTES ratio. The non-isothermal kinetic degradation by thermogravimetric analysis in different heating rates was studiedin order to evaluate the kinetic triplet: activation energy E_a, exponential factor (A), and reaction order (f(α)). The Ea dependence on conversion degree was not affected, but two degradation steps were observed for all samples. Ratios up to 1:4 suggested two consecutive autocatalytic degradation mechanisms. The 1:5 and 1:10 ratios caused a change in the most probable degradation mechanism for nucleation followed by autocatalytic degradation mechanism.

Keywords: Degradation mechanism; Kinetics; Microcrystalline cellulose; Silane; Surface modification.