Crystalline morphology of thermoplastic starch/talc nanocomposites induced by thermal processing

A structural study about the changes induced by plasticization of native corn starch was carried out in this work. The influence of talc nanoparticles presence during starch thermal processing was also evaluated. Macroscopic observation of the granules appearance evolution during melt-mixing and the...

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Detalhes bibliográficos
Autores: Castillo, Luciana A., López, Olivia Valeria, García, María Alejandra, Barbosa, Silvia E., Villar, Marcelo A.
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2019
País:Argentina
Recursos:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/121785
Acesso em linha:http://sedici.unlp.edu.ar/handle/10915/121785
Access Level:acceso abierto
Palavra-chave:Ciencias Exactas
Materials science
Native corn starch
Talc nanoparticles
Thermal processing
Polymorphic transformations
Structural changes
Descrição
Resumo:A structural study about the changes induced by plasticization of native corn starch was carried out in this work. The influence of talc nanoparticles presence during starch thermal processing was also evaluated. Macroscopic observation of the granules appearance evolution during melt-mixing and thermo-compression was supported by a theoretical description related to these processing methods. Melt-mixing induced a polymorphic transformation from A- to V<sub>h</sub>-type and a reduction in the degree of crystallinity. Homogenous appearance of the plasticized starch was in accordance to the disruption of granules integrity, evidenced by SEM. This observation agreed to the distinctive XRD pattern of plasticized starch from unprocessed granules. Talc incorporation did not require the adjustment of processing parameters in order to obtain a homogenous thermoplastic material, with an adequate particles distribution within the matrix. Regardless talc presence, plasticized starch presented a V<sub>h</sub>-type crystalline structure. Thermo-compression led to particles alignment promoted by talc laminar morphology.