Thermal behaviour of ethynyl and ethenyl terminated imide resins

A series of ethynyl and ethenyl end-capped imide resins were synthesised by the reaction of 9,9-bis(4-aminophenyl) fluorene (BAF) with pyromellitic dianhydride (PMDA)3/3′, 4,4′-benzophenone tetracarboxylic acid dianhydride (BTDA)/2,2-bis(3,4-dicarboxy phenyl) hexafluoropropane dianhydride (6F) and 3-ethynyl aniline/maleic anhydride. Structural characterisation was done by infra red and elemental analysis. Thermal characterisation was done by differential scanning calorimetry and thermogravimetric analysis. The decomposition temperatures of cured resins were above 200°C in nitrogen atmosphere. Char yield at 800°C ranged from 59–65.5%.     

Phosphorus-containing imide resins. III

Three imide monomers were prepared by reacting maleic anhydride; 2,2-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride, bis(m-aminophenyl) methyl phosphine oxide, and tris(m-aminophenyl) methyl phosphine oxide, and tris (m-aminophenyl) phosphine oxide. The characterization was done by elemental analysis and infrared spectroscopy (IR). These monomers were soluble in acetone. Their thermal polymerization was investigated by differential scanning calorimetry (DSC). The temperature of the exothermic peak position was influenced by the presence of free amino group in the monomer and was about 50°C higher in monomers that did not contain amino group. Anaerobic char yield of imide monomers cured at 270 ± 2°C for 30 min ranged from 58 to 64%. Graphite cloth laminate fabricated from one of these resins had a limiting oxygen index of 100.     

Organosoluble and thermally stable polyimides derived from a new diamine containing bulky-flexible triaryl pyridine pendent group

A novel kind of aromatic diamine,N-(4-(4-(2,6-diphenyl pyridine-4-yl)phenoxy)phenyl)-3,5-diaminobezamide (DPDAB),was synthesized via aromatic nucleophilic substitution of 3,5-dinitrobenzoylchloride with 4-(4-(2,6- diphenylpyridine-4-yl)phenoxy)aniline(DPPA),followed by palladium-catalyzed hydrazine reduction.This monomer was used to prepare polyimides(PIs)based on reaction with several commerically avaiable tetracarboxylic dianhydrides such as pyromellatic dianhydride(PMDA),benzophenone tetracarboxylic acide dianhydride(BTDA)and bicycle[2.2.2]oct-7-enc- 2,3,5,6-tetracarboxylic dianhydride(BCDA).These PIs had inherent viscosity in the range of 0.34-0.76 dL/g and showed good solubility in various aprotic polar solvents.The glass-transition tempratures(T_gs)of the PIs were in the range of 184-302℃,and showed high thermal stability with 10%weight loss in the temperature range of 360-500℃under nitrogen atmosphere.     

Synthesis and characterization of new aromatic poly(amide-imide)s derived from bis(3-trimellitimidophenyl) phenyl phosphine oxide and various aromatic diamines

New aromatic poly(amide-imide)s with high inherent viscosities were prepared by direct polycondensation reaction of diimide-diacid (I) and aromatic diamines using triphenyl phosphite in N-methyl-2-pyrrolidone (NMP)/pyridine solution containing dissolved CaCl₂. The bis(3-trimellitimidophenyl) phenyl phosphine oxide (I) was readily obtained by the condensation reaction of bis(3-aminophenyl) phenyl phosphine oxide (BAPPO) with trimellitic anhydride. The resulting poly(amide-imide)s showed high thermostability. Their decomposition temperatures at 10% weight loss in nitrogen atmosphere were above 532 °C and the anaerobic char yield at 800 °C ranged from 56% to 74%. Almost all the poly(amide-imide)s showed high glass transition temperature above 233 °C by differential scanning calorimetry (DSC) measurements. These polymers were readily soluble in various organic solvents and by their casting into transparent, tough and flexible films can be easily achieved.     

Curing kinetics and thermal stability of diglycidyl ether of bisphenol

Curing kinetics of diglycidyl ether of bisphenol-A (DGEBA) in the presence of varying molar ratios of aromatic imide-amines and 4,4′-diaminodiphenylsulfone (DDS) were investigated by the dynamic differential scanning calorimetry. The imide-amines were prepared by reacting 1 mole of benzophenone 3,3′,4,4′-tetracarboxylic acid dianhydride (B) with 2.5 moles of 4,4′-diaminodiphenyl ether (E)/ or 4,4′-diaminodiphenyl methane (M)/ or 4,4′-diaminodiphenylsulfone (S) and designated as BE/ or BM/ or BS. The mixture of imide-amines and DDS at ratio of 0:1, 0.25:0.75, 0.5:0.5, 0.75:0.25 and 1:0 were used to investigate the curing behaviour of DGEBA. The multiple heating rate method (5, 10, 15 and 20°C min⁻¹) was used to study the curing kinetics of epoxy resins. The peak exotherm temperature was found to be dependent on the heating rate, structure of imide-amines as well as on the ratio of imide-amine: DDS used. A broad exotherm was observed in the temperature range of 180–230°C on curing with mixture of imide-amines and DDS. Curing of DGEBA with mixture of imide-amines and/or DDS resulted in a decrease in characteristic curing temperatures. Activation energy of curing reaction as determined in accordance to the Ozawa’s method was found to be dependent on the structure of amine. The thermal stability of the isothermally cured resins was also evaluated using dynamic thermogravimetry in a nitrogen atmosphere. The char yield was highest in case of resins cured using mixture of DDS: BS (0.25:0.75; EBS-3), DDS: BM (0.5: 0.5; EBM-2) and DDS: BE (0.5: 0.5; EBE-2).     

Synthesis and characterization of polyimides from bis(3‐aminophenyl)‐4‐(1‐adamantyl)phenoxyphenyl phosphine oxide

A novel diamine, bis(3‐aminophenyl)‐4‐(1‐adamantyl)phenoxyphenyl phosphine oxide (mDAATPPO), was synthesized via the Williamson ether reaction of 4‐(1‐adamantyl)phenol and bis(3‐nitrophenyl)‐4‐fluorophenyl phosphine oxide, followed by reduction. The phenol group was prepared by the Friedel–Crafts reaction of 1‐bromoadamantane and phenol, whereas the phosphine oxide group was synthesized by the Grignard reaction of 1‐bromo‐4‐fluorobezene and diphenyl phosphinic chloride, followed by nitration. The monomer and its intermediate compounds were characterized with Fourier transform infrared, NMR, and melting‐point apparatus. The monomer was then used to prepare polyimides with 2,2‐bis(3,4‐dicarboxyphenyl)hexafluoropropane dianhydride, 3,3′,4,4′‐benzophenonetetracarboxylic dianhydride, 4,4′‐oxydiphthalic dianhydride, and pyromellitic dianhydride by the conventional two‐step synthesis: the preparation of poly(amic acid) followed by solution imidization. The molecular weights of the polyimides were controlled to 20,000 g/mol by off‐stoichiometry, and the synthesized polyimides were characterized with Fourier transform infrared, NMR, gel permeation chromatography, thermogravimetric analysis, and differential scanning calorimetry. In addition, the solubility, intrinsic viscosity, dielectric constant, and birefringence of the polyimides were evaluated. Novel polyimides with mDAATPPO exhibited good solubility, high glass‐transition temperatures (290–330 °C), excellent thermal stability (>500 °C), low dielectric constants (2.77–3.01), low refractive indices, and low birefringence values (0.0019–0.0030). © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2567–2578, 2006     

Syntheses and properties of organosoluble polyimides based on 5,5′‐bis[4‐(4‐aminophenoxy)phenyl]‐4, 7‐methanohexahydroindan

A series of organosoluble aromatic polyimides (PIs) was synthesized from 5,5′‐bis[4‐(4‐aminophenoxy)phenyl]‐4,7‐methanohexahydroindan (3) and commercial available aromatic dianhydrides such as 3,3′,4,4′‐biphenyltetracarboxylic dianhydride (BPDA), 4,4′‐oxydiphthalic anhydride (ODPA), 4,4′‐sulfonyl diphthalic anhydride (SDPA), or 2,2′‐bis(3,4‐dicarboxyphenyl) hexafluoropropanic dianhydride (6FDA). PIs (III_c–f), which were synthesized by direct polymerization in m‐cresol, had inherent viscosities of 0.83–1.05 dL/g. These polymers could easily be dissolved in N,N′‐dimethylacetamide (DMAc), N‐methyl‐2‐pyrrolidone (NMP), N,N‐dimethylformamide (DMF), pyridine, m‐cresol, and dichloromethane. Whereas copolymerization was proceeded with equivalent molar ratios of pyromellitic dianhydride (PMDA)/6FDA, 3,3′,4,4′‐benzophenonetetracarboxylic dianhydride (BTDA)/6FDA, or BTDA/SDPA, or ½ for PMDA/SDPA, copolyimides (co‐PIs), derived from 3 and mixed dianhydrides, were soluble in NMP. All the soluble PIs could form transparent, flexible, and tough films, and they showed amorphous characteristics. These films had tensile strengths of 88–111 MPa, elongations at break of 5–10% and initial moduli of 2.01–2.67 GPa. The glass transition temperatures of these polymers were in the range of 252–311°C. Except for III_e, the 10% weight loss temperatures (T_d) of PIs were above 500°C, and the amount of carbonized residues of the PIs at 800°C in nitrogen atmosphere were above 50%. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1681–1691, 1999     

Synthesis and characterization of novel polyimide from bis‐(3‐aminophenyl)‐4‐(trifluoromethyl)phenyl phosphine oxide

A novel diamine, bis‐(3‐aminophenyl)‐4‐(trifluoromethyl)phenyl phosphine oxide (mDA3FPPO), containing phosphine oxide and fluorine moieties was prepared via the Grignard reaction from an intermediate, 4‐(trifluoromethyl)phenyl diphenyl phosphine oxide, that was synthesized from diphenylphosphinic chloride and 4‐(trifluoromethyl)bromobenzene, followed by nitration and reduction. The monomer was characterized by Fourier transform infrared (FTIR), ¹H NMR, ³¹P NMR, ¹⁹F NMR spectroscopies; elemental analysis; melting point measurements; and titration and was used to prepare polyimides with a number of dianhydrides such as pyromellitic dianhydride (PMDA), 5,5′‐[2,2,2‐trifluoro‐1‐(trifluoromethyl)ethyliden]‐bis‐1,3‐isobenzofuranedione (6FDA), 3,3′,4,4′‐benzophenone tetracarboxylic dianhydride (BTDA), and 4,4′‐oxydiphthalic dianhydride (ODPA). Polyimides were synthesized via a conventional two‐step route; preparation of polyamic acids, followed by solution imidization, and the molecular weight were controlled to 20,000 g/mol. Resulting polyimides were characterized by FTIR, NMR, DSC, and intrinsic viscosity measurements. Refractive‐index, dielectric constant, and adhesive properties were also determined. The properties of polyimides were compared with those of polyimides prepared from 1,1‐bis‐(4‐aminophenyl)‐1‐phenyl‐2,2,2‐trifluoroethane (3FDAm) and bis‐(3‐aminophenyl) phenyl phosphine oxide (mDAPPO). The polyimides prepared from mDA3FPPO provided high glass‐transition temperatures (248–311 °C), good thermal stability, excellent solubility, low birefringence (0.0030–0.0036), low dielectric constants (2.9–3.1), and excellent adhesive properties with Cu foils (107 g/mm). © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3335–3347, 2001     

Synthesis and characterization of arylene ether imide reactive oligomers and polymers containing diaryl alkyl phosphine oxide groups

The diamine monomer bis(m-aminophenyl) methyl phosphine oxide (DAMPO) was synthesized via nitration and reduction of diphenyl methyl phosphine oxide. Rigorous purification of this monomer enabled its utilization in the synthesis of high molecular weight poly(ether imide)s. Both thermoplastic materials and thermosetting systems, endcapped with either phthalic or phenylethynylphthalic anhydride, respectively, have been produced. Major emphasis has been placed on polyimides derived from 2,2′-bis(4-(3,4-dicarboxyphenoxy) phenyl) propane dian- hydride, also known as bisphenol-A dianhydride, or BPADA. High molecular weight homo- and copolyimides based on BPADA/DAMPO had glass transition temperature values in the range of 215–223°C, and were totally amorphous. They displayed higher modulus and tensile strength values than the polyetherimide control based on meta-phenylene diamine and also generated high TGA char yields in air. Phenylethynyl crosslinkable materials were effectively cured at 380°C to produce networks that are ductile, very solvent resistant and also generate high char yields, which suggest their possible utilization in fire resistant matrix systems. © 1998 John Wiley & Sons, Ltd.     

Molecular structure and conformation of triphenylsilane from gas-phase electron diffraction and theoretical calculations, and structural variations in H4?nSiPhn molecules (n?=?1–4)

The molecular structure of triphenylsilane has been investigated by gas-phase electron diffraction and theoretical calculations. The electron diffraction intensities from a previous study (Rozsondai B, Hargittai I, J Organomet Chem 334:269, 1987) have been reanalyzed using geometrical constraints and initial values of vibrational amplitudes from calculations. The free molecule has a chiral, propeller-like equilibrium conformation of C ₃ symmetry, with a twist angle of the phenyl groups τ = 39° ± 3°; the two enantiomeric conformers easily interconvert via three possible pathways. The low-frequency vibrational modes indicate that the three phenyl groups undergo large-amplitude torsional and out-of-plane bending vibrations about their respective Si–C bonds. Least-squares refinement of a model accounting for the bending vibrations gives the following bond distances and angles with estimated total errors: r _g(Si–C) = 1.874 ± 0.004 ?, 〈r _g(C–C)〉 = 1.402 ± 0.003 ?, 〈r _g(C–H)〉 = 1.102 ± 0.003 ?, and ∠_aC–Si–H = 108.6° ± 0.4°. Electron diffraction studies and MO calculations show that the lengths of the Si–C bonds in H_4−n SiPh _n molecules (n = 1–4) increase gradually with n, due to π → σ*(Si–C) delocalization. They also show that the mean lengths of the ring C–C bonds are about 0.003 ? larger than in unsubstituted benzene, due to a one hundredth angstrom lengthening of the C_ipso–C_ortho bonds caused by silicon substitution. A small increase of r(Si–H) and decrease of the ipso angle with increasing number of phenyl groups is also revealed by the calculations.     

Adhesive and dielectric properties of novel polyimides with bis(3,3′-aminophenyl)-2,3,5,6-tetrafluoro-4-trifluoromethyl phenyl phosphine oxide (mDA7FPPO)

Polyimides with a low dielectric constant and excellent adhesion were prepared from a diamine containing phosphine oxide and fluorine groups, bis(3,3′-aminophenyl-2,3,5,6-tetrafluoro-4-trifluoromethyl phenyl phosphine oxide (mDA7FPPO), and rigid-rod type dianhydride containing fluorine groups, such as 3,6-di(3′,5′-bis(trifluoromethyl)-phenyl)pyromellitic dianhydride (12FPMDA). The polyimides were synthesized via the known two-step process, preparation of poly(amic-acid) followed by solution imidization, and characterized by FT-IR, NMR, DSC, TGA and TMA. In addition, their solubility, intrinsic viscosity, dielectric constant and adhesive property were also evaluated. For comparison, 3,6-di(4′-trifluoromethylphenyl) pyromellitic dianhydride (6FPMDA) and 3,6-diphenylpyromellitic dianhydride (DPPMDA) were also utilized. The prepared polyimides exhibited high T_g (276-314 °C), excellent thermal stability (>500 °C in air), good adhesive property (104.7-126.3 g/mm), good solubility, and very low dielectric constant (2.34-2.89).     

Effect of Phosphorus Content on Thermal Behaviour of Diglycidyl Ether of Bisphenol-A/phosphorus Containing Amines

Curing of diglycidyl ether of bisphenol-A (DGEBA) with phosphorus containing amide amines i.e. bis[3(3’-aminobenzamido phenyl)]methyl phosphine oxide (MB),bis[3(4’-aminobenzamido phenyl)]methyl phosphine oxide (PB), tris[3(3’-aminobenzamidophenyl)] phosphine oxide (MT) and tris[3(4’-aminobenzamido phenyl)] phosphine oxide (PT)and conventionally used curing agent 4,4’-diaminodiphenyl sulfone (D) was studied by DSC. The amines MB, PB, MT and PT were synthesised in the laboratory and were characterized by determining elemental composition, melting point, and amine equivalent. Structural characterization was done by ¹H-NMR and FTIR. The onset temperature of curing depended on the nucleophilicity of the amines and was in the orderMT≈MB<PT<PB<D. The exothermic peak temperatures were in the orderD>PB>PT>MT≈MB. The char residue of cured epoxy resin was significantly higher when phosphorus was incorporated in the cured network. Using mixed amine formulations based on amine D and P-containing amines and the molar ratio of these amines could easily control the curing characteristics. A linear relationship between char yield and P-content was observed in such formulations. This revised version was published online in August 2006 with corrections to the Cover Date.     

Synthesis and characterization of 3-phenylethynyl endcapped matrix resins

The synthesis of 3-phenylethynylphenol, and its applicability as a high temperature cross-linking endcap for high T_g polyarylene ethers is described. It was synthesized in high yields and purity using the palladium catalyzed coupling reaction between the protected 3-bromo or iodo phenol and phenylacetylene. The yield of the reaction was found to be highly dependent on the structure of the halide used, the reaction temperature, and the concentration of phenylacetylene. The use of the protected phenol in the palladium catalyzed reaction was also extended to the high yield synthesis of 3-ethynylphenol and protected 4-ethynylphenols. The complete synthesis of 3-phenylethynylphenol, 3-ethynylphenol, and protected 4-ethynylphenol in high yields has been demonstrated and is discussed herein. Three new phenylethynyl functionalized arylene ether matrix resins have been synthesized in high yields and purity by reacting 3-phenylethynylphenol with 4,4′-dichlorodiphenyl sulfone, 4,4′-difluorobenzophenone, and bis(4-fluorophenyl)phenyl phosphine oxide, via nucleophilic poly(arylene ether) synthesis conditions. These low molecular weight materials undergo thermally induced chain extension/branching to yield an insoluble three-dimensional network at reaction temperatures of around 380°C. The low molecular weight arylene ethers endcapped with the phenylethynyl group demonstrate excellent flow characteristics and a wide processing window of about 250°C. Crosslinking of the 4,4′-bis(3-phenylethynyl phenoxy)diphenyl sulfone system for 30 min at 350°C in air afforded a T_g value of 265°C by differential scanning calorimetry measurements. Trace metal analysis for palladium and copper showed absence of these metals that would otherwise detract from the excellent thermal stability. The synthesis and characterization of these phenylethynyl endcapped arylene ether matrix resins is discussed. © 1995 John Wiley & Sons, Inc.     

Kinetic study of crystallization of PHB in presence of hydroxy acids

Poly(3-hydroxybutyrate), PHB, has been structurally modified through reaction with hydroxy acids (HA) such as tartaric acid (TA) and malic acid (MA). The crystallization kinetic of the samples was evaluated by isoconversional method through nonlinear fitting to obtain the estimation for activation energy (E _a ) and pre-exponential (A) values. The thermal behavior of the crystallization temperature, 44.8 and 58.9 °C at 5 °C/min, and results obtained to the average activation energy, 73 ± 9 kJ mol⁻¹ and 63 ± 1 kJ mol⁻¹, to PHB/MA and PHB, respectively, are suggesting that malic acid may be deriving plasticizer units from its own PHB chain. PHB/TA show increase in the medium value of E _a, 119 ± 2 kJ mol⁻¹ and T _c = 48.2 °C (at 5 °C/min), indicating that tartaric acid is probably interacts in different way to the of PHB chain (E _a=73 ± 9 kJ mol⁻¹, T _c = 44.8 °C at 5 °C/min).     

Thermophysical Investigations of the Polymorphous Phases of Calcium Carbonate

1. Results of thermodynamic and kinetic investigations for the different crystalline calcium carbonate phases and their phase transition data are reported and summarized (vaterite: V; aragonite: A; calcite: C). A→C: T _tr=455±10°C, Δ_tr H=403±8 J mol^–1 at T _tr, V→C: T _tr=320–460°C, depending on the way of preparation,Δ_tr H=–3.2±0.1 kJ mol^–1 at T _tr,Δ_tr H=–3.4±0.9 kJ mol^–1 at 40°C, S _V ^Θ= 93.6±0.5 J (K mol)^–1, A→C: E _A=370±10 kJ mol^–1; XRD only, V→C: E _A=250±10 kJ mol^–1; thermally activated, iso- and non-isothermal, XRD 2. Preliminary results on the preparation and investigation of inhibitor-free non-crystalline calcium carbonate (NCC) are presented. NCC→C: T _tr=276±10°C,Δ_tr H=–15.0±3 kJ mol^–1 at T _tr, T _tr – transition temperature, Δ_tr H – transition enthalpy, S ^Θ – standard entropy, E _A – activation energy. 3. Biologically formed internal shell of Sepia officinalis seems to be composed of ca 96% aragonite and 4% non-crystalline calcium carbonate. This revised version was published online in July 2006 with corrections to the Cover Date.     

Thermal decomposition of some linear trinuclear schiff base complexes with acetate bridges

Ni(II)–M(II)–Ni(II) nuclear structured complexes were prepared from N,N’-bis(salicylidene)-1,3-propanediamine (LH2) and its derivatives N,N’-bis(salicylidene)-2,2’-dimethyl-1,3-propanediamine (LDMH₂) and N,N’-bis(salicylidene)-2-hydroxy-1,3-propanediamine (LOH3), where M represents one of the following metal ions; Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II). Two different μ-bridges are found between the metal nucleus of the complexes. The phenolic oxygens and acetate ions tend to form μ-bridges between the terminal Ni(II) ions and central metal(II) ion. The coordinatively bonded DMF molecules, in the complexes, were observed to abandon the structure between 160–180°C. Further heating resulted primarily in the thermal decomposition of the complexes above 310°C, whereas metal oxide residue mixtures were observed above 650°C.     

Synthesis and properties of polyimides from thianthrene-2,3,7,8-tetracarboxylic dianhydride-5,5,10,10-tetraoxide

Thianthrene - 2,3,7,8 - tetracarboxylic dianhydride - 5,5,10,10 - tetraoxide (TADATO), a dianhydride having two sulfonyls between two phenyl rings, was synthesized and polymerized with several diamines by a two-step method. Tough polyimide membranes were obtained with flexible diamines but not with rigid diamines. Most of TADATO-based polyimides are soluble in polar solvents such as N,N-dimethylacetamide and N-methyl-2-pyrrolidone. IR study confirmed that almost complete imidization of TADATO-based poly(amic acid) membranes could be achieved by thermal treatment at 100, 200, and 300°C for each 1 h. In a series of polyimides based on 4,4′-oxydianiline, the polyimide from TADATO showed higher gas permeability coefficient of CO₂ and higher selectivities of CO₂/N₂ and CO₂/CH₄ than those of polyimides from pyromellitic dianhydride and 3,3′,4,4′-biphenyltetracarboxylic dianhydride, and was comparable to that from 2,2-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36 : 485–494, 1998     

Chemical Modification of Polystyrene. VI. Thermal Stability Studies of Sulfonic Acid Resins from Anhydride Modified Polystyrene

Thermal stabilities of the H form of sulfonic acid resins from polystyrene electrophilically substituted with phthalic anhydride, pyro-mellitic dianhydride, trimellitic anhydride, and cis-1,2,3,6-tetra-hydrophthalic anhydride have been studied and compared by DTA and TGA. Isothermal degradation studies of these resins at 150 ± 10°C for 72 h in air and nitrogen reveal significant changes in IR, decreases in sulfur content, and increases in ion-exchange capacity values. The pH-metric titration characteristics of the pyro-mellitic-dianhydride-modified sulfonated polystyrene after isothermal heating under the above conditions indicate weak acid behavior, in contrast to the strong acid nature of the original resin.     

Preparation and characterisation of NdAlO<Subscript>3</Subscript> nanocrystals by modified sol–gel method

Nanocrystalline single-phase neodymium monoaluminate (NdAlO₃) has been prepared from neodymium oxide and aluminium nitrate by modified Pechini’s method. Malic acid has been used for the first time as a new complexing agent in the sol–gel process. It has facilitated, without adding 1,2-ethanediol, a low-temperature synthesis at 1,050 °C compared to the temperature of 1,630 °C needed for the solid-state preparation. The characterisation of the nanoparticles has been carried out by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and infrared spectroscopy in the range 75–4,000 cm⁻¹. The smallest particles have size of 30 nm and are anisometric; agglomerates of particles have been also observed. The material has pyknometric density of 3.956 g/cm³ at T = 293.15 K and specific surface area 5.2 m²/g. The binding energies of O 1s, Al 2p, Nd 3d, and Nd 4d electrons have been found chemically shifted in NdAlO₃ compared to the values for the respective elements.