A study by X-ray of the crystal structure of syndiotactic l,2-poly(1,3 -butadiene) as a function of the temperature is reported. X-ray powder profiles have been collected at various temperature from -20°C up to 120°C. All the profiles have the same shape, slightly differing only in the positions of the various reflections, caused by the expansion of the unit cell with the increase of the temperature. The trends of the a and b axes as a function of the temperature are linear and, therefore, constant values of the thermal expansion coefficients have been determined. They are 2.8•10-4 K-1 and 6.7•10-5 K-1, respectively. These values are similar, or at least of the same order of magnitude, to those found previously for other vinyl polymers.
DETERMINAZIONE DEGLI ASSI DELLA CELLA ELEMENTARE DEL 1,2 POLI(1,3-BUTADIENE) SINDIOTATTICO IN FUNZIONE DELLA TEMPERATURA / Napolitano, Roberto; Pirozzi, Beniamino; S., Esposito. - STAMPA. - (2005), pp. 230-231. (Intervento presentato al convegno XVII Convegno Italiano di Scienza e Tecnologia delle Macromolecole tenutosi a Napoli nel 11-15 settembre 2005).
DETERMINAZIONE DEGLI ASSI DELLA CELLA ELEMENTARE DEL 1,2 POLI(1,3-BUTADIENE) SINDIOTATTICO IN FUNZIONE DELLA TEMPERATURA
NAPOLITANO, ROBERTO;PIROZZI, BENIAMINO;
2005
Abstract
A study by X-ray of the crystal structure of syndiotactic l,2-poly(1,3 -butadiene) as a function of the temperature is reported. X-ray powder profiles have been collected at various temperature from -20°C up to 120°C. All the profiles have the same shape, slightly differing only in the positions of the various reflections, caused by the expansion of the unit cell with the increase of the temperature. The trends of the a and b axes as a function of the temperature are linear and, therefore, constant values of the thermal expansion coefficients have been determined. They are 2.8•10-4 K-1 and 6.7•10-5 K-1, respectively. These values are similar, or at least of the same order of magnitude, to those found previously for other vinyl polymers.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
