| Full text | |
| Author(s): |
Total Authors: 3
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| Affiliation: | [1] Univ Estadual Campinas, UNICAMP, Dept Engn Mat & Bioproce, Fac Engn Quim, Campinas, SP - Brazil
Total Affiliations: 1
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| Document type: | Journal article |
| Source: | MATERIALS RESEARCH-IBERO-AMERICAN JOURNAL OF MATERIALS; v. 21, n. 6 2018. |
| Web of Science Citations: | 0 |
| Abstract | |
The effect of clay hydrophobicity on the cold crystallization and rheological properties of nanocomposites of poly(D,L-lactic acid) (PDLLA) was investigated. Crystallization was evaluated by DSC for isothermal and non-isothermal conditions. The clay modified with a hydrophilic surfactant acts as a nucleating agent, while the clay modified with a hydrophobic surfactant acts in an opposite way. The Avrami and Ozawa parameters showed a three-dimensional spherulitic growth for all samples and the activation energy increased for the hydrophobic clay and decrease for the hydrophilic one. The equilibrium melting point for the PDLLA was found at 161 degrees C, being slightly altered as function of the surfactant polarity. The rheological behavior was investigated in terms of Isothermal Flow-Induced Crystallization and Structural Recovery. The hydrophobic clay showed to reduce the mobility of chains and retard the chain relaxation, which is attributed to the formation of a network, while the hydrophilic clay increased the chain mobility. (AU) | |
| FAPESP's process: | 12/00227-2 - Study of PLA/organoclays nanocomposites: characterization, biodegradation and genotoxic and mutagenic effects |
| Grantee: | Ana Rita Morales |
| Support Opportunities: | Regular Research Grants |
| FAPESP's process: | 11/14250-3 - Study of influence of organoclays on biodegradation process of PLA nanocomposites and its genotoxic and mutagenic effects. |
| Grantee: | Patrícia Moraes Sinohara Souza |
| Support Opportunities: | Scholarships in Brazil - Master |