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Avanzar en el desarrollo de policarbonatos a base de glucosa altamente funcionalizables mediante el ajuste de la
Yue Song, Xiaozhou Ji, Mei Dong
1College of Medicine , Texas A&M University , Bryan , Texas 77807 , United States.
Journal of the American Chemical Society
|November 13, 2018
Resumen
Los investigadores ajustaron la temperatura de transición de vidrio (Tg) de los polímeros a base de productos naturales mediante la alteración de las cadenas laterales. Esta adaptabilidad es clave para el desarrollo de policarbonatos avanzados a base de glucosa con diversas propiedades térmicas.
Área de la Ciencia:
- Química de los polímeros
- Ciencias de los materiales
- Química orgánica
Sus antecedentes:
- Los polímeros a base de productos naturales ofrecen propiedades ajustables para diversas aplicaciones.
- Comprender los factores que influyen en las propiedades del polímero es crucial para el diseño de materiales.
- Los polímeros a base de glucosa son una clase prometedora de materiales renovables.
Objetivo del estudio:
- Investigar la afinidad de la temperatura de transición de vidrio (Tg) en el policarbonato lineal de glucosa.
- Para correlacionar las variaciones de Tg con la estructura de la cadena lateral y la masa molar.
- Avanzar en el desarrollo de policarbonatos funcionalizables a base de glucosa.
Principales métodos:
- Síntesis y fraccionamiento de policarbonatos lineares y oligómeros discretos con grados de polimerización controlados.
- Variación sistemática de las cadenas laterales de alquiloxicarbonilo para modificar la estructura del polímero.
- Medición de la temperatura de transición de vidrio (Tg) en una gama de polímeros sintetizados.
Principales resultados:
- Se logró un amplio rango de valores de Tg, de 38 a 125 °C, modificando seis cadenas laterales de alquiloxicarbonilo diferentes.
- Se ha demostrado que Tg está significativamente influenciado por los efectos sinérgicos de la flexibilidad de la cadena lateral, la voluminosidad y el volumen libre del extremo de la cadena.
- Se estableció una clara relación entre la estructura del polímero (cadena lateral y masa molar) y las propiedades térmicas.
Conclusiones:
- La ingeniería de la cadena lateral proporciona una poderosa estrategia para ajustar las propiedades térmicas de los policarbonatos a base de glucosa.
- Los resultados permiten el diseño racional de polímeros a base de glucosa con temperaturas específicas de transición de vidrio para aplicaciones específicas.
- Este estudio pone de relieve el potencial de la simple modificación de la cadena lateral para crear materiales con diversas características físico-químicas y térmicas.
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