Publications

@article{Islam2020-al,

title = {The effect of MgO/TiO2 on structural and crystallization 

 behavior of near invert phosphate-based glasses},

author = {Md Towhidul Islam and Nusrat Sharmin and Graham A Rance and Jeremy J Titman and Andrew J Parsons and Kazi M Zakir Hossain and Ifty Ahmed},

year  = {2020},

date = {2020-04-01},

journal = {J. Biomed. Mater. Res. B Appl. Biomater.},

volume = {108},

number = {3},

pages = {674\textendash686},

publisher = {Wiley},

abstract = {Varying formulations in the glass system of 40P2 O5 ─(24 - 

 x)MgO─(16 + x)CaO─(20 - y)Na2 O─yTiO2 (where 0 $\leq$ x $\leq$ 22 and y = 0 or 1) were prepared via melt-quenching. The 

 structure of the glasses was confirmed by X-ray diffraction 

 (XRD), Fourier transform infrared (FTIR), micro Raman and 

 solid-state nuclear magnetic resonance (NMR) spectroscopies. The 

 thermal properties and the activation energy of crystallization 

 (Ec ) were measured using thermal analysis and the Kissinger 

 equation, respectively. The glass forming ability of the 

 formulations investigated was seen to decrease with reducing MgO 

 content down to 8 mol% and the glass stability region also 

 decreased from 106 to 90°C with decreasing MgO content. The 

 activation energy of crystallization (Ec ) values also decreased 

 from 248 (for 24 mol% MgO glass) to 229 kJ/mol (for the 8 mol% 

 MgO content) with the replacement of MgO by CaO for glasses with 

 no TiO2 . The formulations containing less than 8 mol% MgO 

 without TiO2 showed a strong tendency toward crystallization. 

 However, the addition of 1 mol% TiO2 in place of Na2 O for 

 these glasses with less than 8 mol% MgO content, inhibited 

 their crystallization tendency. Glasses containing 8 mol% MgO 

 with 1 mol% TiO2 revealed a 12°C higher glass transition 

 temperature, a 14°C increase in glass stability against 

 crystallization and a 38 kJ/mol increase in Ec in comparison to 

 their non TiO2 containing counterpart. NMR spectroscopy revealed 

 that all of the formulations contained almost equal percentages 

 of Q1 and Q2 species. However, FTIR and Raman spectroscopies 

 showed that the local structure of the glasses had been altered 

 with addition of 1 mol% TiO2 , which acted as a network 

 modifier, impeding crystallization by increasing the 

 cross-linking between phosphate chains and consequently leading 

 to increased Ec as well as their glass forming ability.},

keywords = {activation energy, biomaterials, crystallization, phosphate   glass},

pubstate = {published},

tppubtype = {article}

}