Solubility and Diffusion Coefficient of Carbon Dioxide in Biodegradable Polymers

Abstract

The solubility and diffusion coefficient of carbon dioxide in the biodegradable polymers poly(butylene succinate) and poly(butylene succinate-co-adipate) were measured at temperatures from 323.15 to 453.15 K and pressures up to 20 MPa. The solubilities in the polymer's molten state increased linearly with pressure and decreased with temperature. Solubilities could be correlated to within 2.2% by the Sanchez−Lacombe equation of state in conjunction with a temperature-dependent interaction parameter. The Sanchez−Lacombe equation of state was also found to be applicable to the correlation of solubilities in the semicrystalline state. The interaction parameter determined from fitting the solubility was inversely proportional to temperature. The diffusion coefficients of carbon dioxide showed a weak concentration dependence and had an order of magnitude of 10-9 m2/s in the molten state. The diffusion coefficients were correlated with the free-volume model of Kulkarni and Stern.

Effect of pressure and temperature on interfacial tension of poly lactic acid melt in supercritical carbon dioxide

“…Details about the experimental apparatus and procedure can be found in previous publications [17][18][19], however, a brief overview of the solubility measurement is as follows. At vacuum (P=0) and temperature T, polymer pellets were weighed as W (0, T) from the balance readout.…”

“…Then, using the obtained weights, the amount of gas dissolved in the polymer melt, Wg, was calculated as below [20]:…”

Solubility measurements of N2 and CO2 in polypropylene and ethene/octene copolymer

“…Sato et al 15,16 have investigated the solubilities of CO 2 and N 2 in PS, PP, and HDPE using a pressure decay approach. They also have extensively measured the solubilities of CO 2 and N 2 in PS, PVAC, PBS, and PPO/PS blends with a magnetic suspension balance (MSB), [17][18][19] while Areerat et al have utilized the MSB to evaluate the solubility of CO 2 in LDPE. 20 Wong et al 21 explored the solubility of CO 2 in PS and PVC using an electrobalance.…”

Effect of Pressure on the Melting Point of Pluronics in Pressurized Carbon Dioxide

“…The depression in melting point (T m ) or glass transition (T g ) temperature in polymers due to the sorption of CO 2 is a well-known phenomenon which is dependent on various factors such as crystallinity and presence of CO 2 -philic moieties [9][10][11][12][13][14] . Amorphous polymers are reported to show higher interactions with CO 2 than crystalline polymers 15,16 .…”