Jump to main content
Jump to site search

Issue 37, 2014
Previous Article Next Article

Sandwich crystals of butyl paraben

Author affiliations


Butyl paraben crystals having a porous layer in between two solid non-porous layers have been produced by cooling crystallization in mixtures of ethanol and water. The outer layers are transparent and fully crystalline, while the middle layer appears to be polycrystalline and is full of pores of various dimensions, down to below 0.1 μm diameters. The thickness of the porous layer reaches about 40% of the whole crystal. The crystals contain one polymorph only and appear to be essentially fully crystalline. They are stable for more than a year when stored on the shelf at room temperature. When the crystals dissolve, the porous layer dissolves faster, leaving the outer layers for slower dissolution. The sandwich crystals are easily cleaved through the middle layer parallel to the (100) plane. This type of sandwich crystals may provide new useful properties to pharmaceutical solids, e.g. larger specific surface area, higher dissolution rates and improved compaction properties.

Graphical abstract: Sandwich crystals of butyl paraben

Back to tab navigation

Supplementary files

Article information

29 Jun 2014
30 Jul 2014
First published
30 Jul 2014

CrystEngComm, 2014,16, 8863-8873
Article type
Author version available

Sandwich crystals of butyl paraben

H. Yang, H. Chen and Å. C. Rasmuson, CrystEngComm, 2014, 16, 8863
DOI: 10.1039/C4CE01320D

Social activity

Search articles by author