| Texto completo | |
| Autor(es): |
Fonseca, Lucas Polo
Número total de Autores: 1
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| Tipo de documento: | Artigo Científico |
| Fonte: | MACROMOLECULAR RESEARCH; v. N/A, p. 13-pg., 2023-03-09. |
| Resumo | |
Amphiphilic hyperbranched polyurethanes (HPUs) based on PEG and PCL are promising for several biomedical applications. However, the lack of control over the molar mass and composition hinders a deep understanding of the aqueous self-assembly of HPUs. In this paper, the control over the HPU molar mass and composition was provided by dynamic urea bond-mediated polymerization (DUBMP), enabling a careful evaluation of their aqueous self-assembly by H-1 NMR, DLS, and Cryo-TEM. HPUs containing a single PCL block per chain self-assemble into nanoaggregates (R-h approximate to 10 nm) in water up to its cloud-point temperature (T-cp) of 34 degrees C. On the other hand, HPUs with more than one PCL block per chain self-assemble into nanoaggregates and their clusters below Tcp. In this case, the solution behavior can be tuned by the HPU molar mass. Increasing MW from 4 to 19 kDa, HPUs of similar composition can form colloidally stable cluster suspensions ((M) over bar (W) = 4 kDa) and phase separate into a denser liquid aggregate-cluster phase ((M) over bar (W) = 7 kDa) or into a highly viscous aggregate-network phase ((M) over bar (W) = 19 kDa). This type of control over the hierarchical aggregation of HPUs was reported for the first time and is interesting for biomedical applications. [GRAPHICS] . (AU) | |
| Processo FAPESP: | 15/25406-5 - Organizando a matéria: colóides formados por associação de surfactantes, polímeros e nanopartículas |
| Beneficiário: | Watson Loh |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |