Elastic and inelastic compression effects in polymer mercury porometry

Krasnov, E. P.; Dronnikov, V. V.; Kruglova, G. S.

doi:10.1007/bf00855893

Cited by 1 publication

(2 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, for many years, there have been doubts about the reliability of results obtained by this method operating at the pressure of thousands of bars. 9 Particularly in polymers, whose structure is usually flexible, one can obtain confusing results if their porosity changes temporarily during measurement and is restored afterward. Finally, some of the highest requirements are imposed on porous polymers that are designed to repair bones.…”

Section: ■ Introductionmentioning

confidence: 99%

“…Even higher pressures are exerted when a porous polymer serves as a column filler in high-pressure liquid chromatography. , Numerous applications of macroporous polymers make them an object of mercury porosimetry studies. However, for many years, there have been doubts about the reliability of results obtained by this method operating at the pressure of thousands of bars . Particularly in polymers, whose structure is usually flexible, one can obtain confusing results if their porosity changes temporarily during measurement and is restored afterward.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Mechanical Stability of Porous Copolymers by Positron Annihilation Lifetime Spectroscopy

2015

View full text Add to dashboard Cite

A set of porous copolymer samples (VP-TRIM, VP-DVB, and VP-DMN) under mechanical stress up to 1.3 GPa was studied in situ using positron annihilation lifetime spectroscopy. A few stages of porosity evolution dissimilar in changes of the pore size distribution (PSD) were observed. At low pressure, the maximum of PSD and the pore volume decreased, indicating pore shrinkage. Simultaneously, the fast decrease in the width of PSD shows that the size of the largest pores is mostly reduced. In copolymers in which the number of relatively weak ester bonds is significant, an additional stage exists at 40−70 MPa. In this range, the trend of the changes in the width of PSD versus pressure is reversed, indicating pore reorganization (probably, they connect with each other). Above a certain pressure (0.2−0.5 GPa), both the maximum and the width of PSD stabilize at minimal values, ca. 1−2 nm. These values as well as the stabilization pressure are specific for each polymer. Pore collapse is observed in a high-pressure range, where only the pore volume decreases. The pores are completely closed at 0.8−1.3 GPa (depending on the polymer), but their porosity is greatly recovered after pressure release. The size and volume of the pores after porous polymer squeezing depend on the maximal exerted pressure.

show abstract

Section: ■ Introductionmentioning

confidence: 99%