The existence region and composition of a polymer-induced liquid precursor phase for dl-glutamic acid crystals

Abstract

The existence region of a polymer-induced liquid precursor (PILP) phase for crystals of an organic compound (DL-glutamic acid, Glu) was determined for the first time in the phase diagram of the Glu-polyethyleneimine-water-ethanol system. The existence region and the amount of PILP phase relative to the thermodynamically stable crystal phase were very small. Other phases detected in the phase diagram were coacervates, homogenous mixtures, and crystals obtained via a clear solution. The PILP phase is rich in the polymeric additive, which helps to explain the long induction period of PILP before crystallization occurs. Volume measurements indicated that its amount is <<1 vol%, showing that this precursor phase is only a minor component.

Molecular Simulation of CO2- and CO3-Brine-Mineral Systems

“…These studies were unable to convincingly demonstrate that the observed particles were indeed liquid rather than amorphous and solid. However, from the biomineralization literature it is well known that organic molecules can stabilize a metastable liquid form of calcium carbonate called PILP (Polymer Induced Liquid Precursor) (Gower and Odom 2000;Jee et al 2011;Jiang et al 2012). It therefore seems plausible that a dense liquid phase may also form in the absence of organics, with the inorganic liquid state being presumably less stable than PILP.…”

Polymer-Mediated Growth of Crystals and Mesocrystals

“…If PILPs are used to generate thin films, these films can have a hierarchical structure and can also be mesocrystalline ( Jiang, Gong, Volkmer, Gower, & Coelfen, 2011;Jiang et al, 2013). The biggest disadvantage of PILP is that it is only present in a very small region of the phase diagram, as shown in the phase diagram of the glutamic acidpolyethyleneimine system (Jiang, Gower, Volkmer, & Coelfen, 2012). Since this is the solvent-rich region in the phase diagram with only a small amount of the crystallizing component, it is not possible to generate large amounts of PILP to use them in large-scale applications.…”

From Solute, Fluidic and Particulate Precursors to Complex Organizations of Matter

“…(d) In situ observations of LCPs as precursors for amorphous and crystalline metal particles in supersaturated Au 0 solutions . Polymer stabilized LCPs observed during the growth of (e,f) strontium carbonate crystals, (g) hierarchical microspheres of DL‐glutamic acid and (h) irregular citrate microcrystals . [Reproduced with permissions from (a, d) Springer Nature, (b) John Wiley and Sons, (c) Royal Society of Chemistry, (e–g) American Chemical Society and (h) Springer Berlin Heidelberg].…”

“…Contributions of gold‐gold atom interactions and water‐associated metastable gold complexes are suggested in these structural developments. Exemplifying organic materials (Figure g,h), the existence of LCP phases is demonstrated by PILPs composed of DL‐glutamic acid or citrate stabilized by polyethyleneimine (PEI) ,. Although the corresponding phase diagram identifies a small existence region of PILP phases relative to the thermodynamically stable crystalline forms, the long induction period for crystallization has enabled the characterization and manipulation of the fluidic material precursors .…”

“…Exemplifying organic materials (Figure g,h), the existence of LCP phases is demonstrated by PILPs composed of DL‐glutamic acid or citrate stabilized by polyethyleneimine (PEI) ,. Although the corresponding phase diagram identifies a small existence region of PILP phases relative to the thermodynamically stable crystalline forms, the long induction period for crystallization has enabled the characterization and manipulation of the fluidic material precursors . At present, an intense exploration of diverse LCP precursors is underway from fundamental perspectives of the formation and growth of diverse materials as well as with prospects of fabricating remarkable architectures, which are difficult to achieve via classical crystallization.…”