In recent years, a rapidly growing interest in metal-organic frameworks (MOFs) has emerged on account of their chemical tuneability, versatile structures and unique physical properties. MOFs comprise metal ions or clusters known as secondary building units (SBUs) and multidentate organic linkers. Various potential applications of MOFs have been suggested; these include drug delivery, heterogenous catalysis, water harvesting, gas storage and separation, and optical sensing. In addition to their porous architectures and high internal surface areas, an interesting phenomenon has emerged whereby several MOFs can be melt-quenched to form a MOF glass. A glass is considered an amorphous material that exhibits a transition from a brittle solid to a viscoelastic state over a specific temperature range, characterised by the glass transition temperature (Tg). A large proportion of known MOF glasses are melt-quenched from crystalline zeolitic imidazolate frameworks (ZIFs), a subgroup of MOFs, which consist of tetrahedrally-coordinated metal ions (e.g. Zn , Co ) and imidazolate or imidazolate-derived linkers. A crystalline ZIF that has excellent glass forming ability is ZIF-62, [Zn(Im)1.75(bIm)0.25] where Im = imidazolate (C3H3N2 -) and bIm = benzimidazolate (C7H5N2 -) (Figure ). Suggested applications of ZIF-62 glass (agZIF-62) include energy storage, catalysis and lithium-ion batteries. Additionally, the use of agZIF-62 as gas separation membranes has also been studied, because it retains 50% of the porosity of crystalline ZIF-62 post melt-quenching, whilst avoiding issues arising from defects and grain boundaries associated with membranes composed of polycrystalline materials. Several studies have focused on combining agZIF-62 with other materials, such as crystalline MOFs, carbon black, lead halide perovskites and organic materials to form composite membranes. Currently, phosphate glasses are of interest to a multitude of industries as laser hosts, biomaterials, proton conductors, and in nuclear waste immobilisation and remediation. Structurally, phosphate glasses are based on the network former P2O5 with PO4 building blocks interconnected via bridging oxygen atoms (Figure ). These polyhedra can be described by Q n notation, where n is the number of bridging oxygen atoms per tetrahedra. Unmodified phosphate glasses comprise Q 3 groups which contain a phosphorous atom with one P=O and connected to three bridging oxygen atoms. This intrinsic non-bridging oxygen (NBO) is responsible for the lower melting temperatures (Tm), Tgs and higher melt fragilities of phosphate glasses when compared to similar silicate and germanate glasses. For binary ultraphosphate glasses, such as sodium ultraphosphate glasses xNa2O(1-x)-P2O5, where 0 ⩽ x ⩽ 0.5, Q 2 and Q 3 groups are the dominant species. 26 Q 3 species, described above, contain a P=O bond, whereas Q 2 species contain a phosphorous atom connected to two bridging atoms. Upon the addition of modifiers such as alkali and alkali earth metal oxides to vitreous P2O5 (i.e., 100% P2O5 glass), the P-O-P bonds throughout the glass are disrupted via the conversion of these bridging oxygen species to NBOs. The subsequent reduction in network connectivity decreases the Tg of the modified glass. When sodium oxide is introduced to the phosphate network, various structural motifs (Figure ) have been identified, in which sodium ions form ionic bonds with the oxygen atoms in the Q 2 and Q 3 units. A potential advantage of blending two glasses is avoiding the drawbacks associated with the constituent parent materials. Blending is well-established in polymer mixing in the plastics industry, where a blend can be considered a macroscopically homogenous mixture of two or more different species. MOF glasses exhibit elastic moduli in between those of inorganic glasses (brittle yet scratch resistant) and organic polymers (ductile yet scratch prone). In the case of agZIF-62 however, workability (i.e., the degree to which a material can be shaped without crack formation) is hampered by a high viscosity in the molten phase, which makes it hard to cast into different morphologies. As such, producing bulk, bubble-free agZIF-62 remains a substantial challenge, owing to the high viscosity (η = 10 5.1 Pa•s) at the Tm (~ 437 °C) of crystalline ZIF-62. On the other hand, ultraphosphate glasses are hygroscopic and combining them with a hydrophobic glass could improve their stability.