Nanocomposites and nanomaterials 

Polymorphism in the nanocomposites of the nanomaterial laponite and triphenyl phosphite 
Baran J.1, Davydova N.A.2, Drozd M. 1, Krivchikov A.I. 3,
Reznichenko V. Ya.2
1 Institute of Low Temperature and Structure Research, PAS, 2 Okólna Str., 50-422 Wrocław, Poland.
2 Institute of Physics, NASU, 46 pr. Nauki, Kiev 03028, Ukraine.
E-mail: Davydova@iop.kiev.ua
3B. Verkin Institute for Low Temperature Physics and Engineering of NASU, 47 pr. Nauki,  Kharkiv 61103, Ukraine.

     Triphenyl phosphite [TPP, P(OPh)3] is a simple molecular liquid at room temperature. The interest to this compound caused by the discovery of a new, apparently amorphous phase, named glacial phase [1]. Laponite a is synthetic smectic clay with the general formula Na+0.7[(Si8Mg5.5Li0.3)O20(OH)4]−0.7 [2].  Laponite is made up of small disc-like particles. Each single-particle is a crystalline disc with an average diameter of 25 nm and a thickness of 1.0 nm [2]. To create TPP/laponite nanocomposite to liquid TPP (1 cm3) the powder laponite with mass of 0.3 g was added. 
    A question arises whether it is possible to turn the physical properties of TPP by adding the laponite nanoparticles into pure TPP. Results presented here show that, the interaction between the liquid TPP and laponite nanoparticles gives rise to different polymorphic forms with melting temperatures 293, 299 and 309 K, in addition to the already known stable crystalline phase of TPP whose crystallization occurs at 240 K (melting point 295 K) and metastable crystalline phase of TPP whose crystallization occurs at 260 K (melting point 291.6 K) [3]. At the same time the addition of laponite nanoparticles to pure TPP leads to the impossibility of forming a glacial phase in nanocomposite.  

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2. Fatnassi M., Es-Souni M. Nanoscale phase separation in laponite-polypyrole nanocomposites // Royal Soc. Chem. – 2015. – 5. – P. 21550-21557.
3. Baran J., Davydova N.A., Drozd M. // The J. Chem. Phys.-2014. – 140. – P. 104512-104518.