Empirical Formula: C₂₀H₁₄O₄
Molecular Weight: 318.3228
IUPAC Name: Diphenyl benzene-1,3-dicarboxylate 
EINECS: 212-014-6
Product Categories: Pharmaceutical Intermediates; Miscellaneous; Functional Materials; Liquid Crystals & Related Compounds; Phenyl Esters (Liquid Crystals); C12 to C63; Carbonyl Compounds; Esters
Nominal Mass: 318
Average Mass: 318.3228 
Monoisotopic Mass: 318.089209
Index of Refraction: 1.615
Molar Refractivity: 89.54 cm³
Molar Volume: 256.2 cm³
Surface Tension: 50.1 dyne/cm
Density: 1.242 g/cm³
Flash Point: 255.3 °C
Enthalpy of Vaporization: 76.49 kJ/mol
Boiling Point: 497 °C at 760 mmHg
Melting Point: 136-138 °C(lit.)
Water Solubility: insoluble
Vapour Pressure of Diphenyl isophthalate (CAS NO.744-45-6): 5.15E-10 mmHg at 25 °C 

It is a monomer of PBT heat-resistant polymer and used as plasticizers of Nylon resins.Besides,it also can be used as raw materials for aromatic heterocyclic polymer and toughening polyamide engineering plastics.

Safety Statements: 24/25
S24/25: Avoid contact with skin and eyes
WGK Germany of Diphenyl isophthalate (CAS NO.744-45-6): 3

 Diphenyl isophthalate (CAS NO.744-45-6), its Synonyms are Diphenyl m-phthalate ; 1,3-Benzenedicarboxylic acid, 1,3-diphenyl ester ; 1,3-Benzenedicarboxylic acid, diphenyl ester ; Isophthalic acid, diphenyl ester (8CI) . It is white to off-white powder.