Low-temperature thermal properties of 2,2-dimethyl-1,3-propanediol and its deuterated analogues

Heat capacity measurement of organic thermal energy storage materials

“…There are no reports of low temperature C p,m of AMPL (T < 280 K) and there is only one dataset for the liquid phase. The C p,m of NPG (T trs = 314.8 K [13], T fus = 403.3 K [13]) first reported by Zhang et al [13] using AC from (270 to 440) K and subsequently by Chandra et al [11] from (305 to 447.5) K. Recently, Kamae et al [14] reported low temperature C p,m of NPG (as well as its deuterated analogues) from (14.9 to 339.89) K. It can be seen that there is a need for further C p,m measurements in the low temperature and liquid region for AMPL and NPG. It is well known that adiabatic calorimetry [15] is a more precise method for measurement of heat capacities and was the predominant mode of conducting thermal analysis experiments during the early 1900s.…”

“…Russell et al [6] summarized transitional enthalpies and temperatures of AMPL, NPG, and TRIS. However, in this study, we compare the values obtained from MDSC primarily to adiabatic calorimetry experiments [9,10,[12][13][14] and to our heat capacity data from conventional d.s.c. experiments reported by Chandra et al [11].…”

“…The focus of experimental thermodynamic studies has been on binary systems, primarily to change the transition temperatures and evaluate the possibility of using binary [11] 23,540 [11] Body center cubic (BCC) 380 [11] 3330 [11] a = 8.613(3) Å , b = 11.037(4) Å , c = 6.105(2) Å , b = 93.57(1)°, Z = 4, T = 293 K [41] 353.72 [12] 23,460 ± 750 [12] a = 6.753(7) Å , Z = 4, T = 353 K [37] 384.08 [12] 2780 ± 50 [12] 355.66 (351.05) ± 0.28 a 23,548 ± 159 a 384.08 (380.26) ± 0.57 a 2755 ± 54 a TRIS Orthorhombic 408 [11] 32,690 [11] Body center cubic (BCC) 445 [11] 3340 [11] a = 8.844(1) Å , b = 7.794(1) Å , c = 8.795(1) Å , Z = 4, T = 295 K [42] 407.56 ± 0.01 [9] 33,420 ± 210 [9] 443.6 ± 0.1 [9] 2410 ± 170 [9] 409.2 (405.12) ± 0.37 a 33,475 ± 440 a a = 6.876(6) Å , Z = 2, T = 423 K [42] 444.57 (440.59) a, * 3104 a, * NPG Monoclinic 313 [11] 13,630 [11] Face center cubic (FCC) 399 [11] 4600 [11] a = 5.979(1) Å , b = 10.876(2) Å , c = 10.099(2) Å , b = 99.78(1)°, Z = 4, T = 293 ± 1 K [43] 314.5 ± 0.1 [14] 12,520 ± 20 [14] a = 8.854(8) Å , Z = 4, T = 314.6 K [37] 314.8 [13] 12,410 ± 80 [13] 403.3 [13] 4440 ± 50 [13] 315.14 (311.18) a, * 12,238 a, * 401.63 (397.13) a, * 4225 a, * * For pure TRIS and NPG, the enthalpy and temperature of fusion is reported only for Dataset 3 and Dataset 2, respectively. For temperaures of transitions the value in pareantheses represents the onset temperature.…”

Phase equilibria and eutectic growth in ternary organic system (D)camphor–neopentylglycol–succinonitrile

“…The table gives the temperatures of the OCs/ODICs phase transitions, the solidus and liquidus temperatures and the values of the enthalpy of phase transitions (enthalpy OCs/ODICs transformation+enthalpy of fusion). The experimental values for pure substances available in the literature [6][7][8][9][10] are also given for comparison with the data obtained in the present work.…”

Melting of orientational degrees of freedom

“…Activation of the orienta- 29 tional degrees of freedom from the completely ordered crystalline phase occurs across 30 a first-order transition with unusual large enthalpy and entropy changes that exceed 31 those associated with the melting towards the liquid phase [1,2]. This has made them 32 promising as solid-state thermal energy storage materials [3,4].…”