Synthesis and Properties of Poly(Phenyl Propargyl Ether) and Its Homologues

Abstract

Various para-substituted phenyl propargyl ethers (substitutent = H, OMe, and CN) were synthesized and polymerized by transition metal catalyst systems including MoCl₅, WC1₆, and PdCl₂. The catalytic activity of MoCl₅-based catalysts was greater than that of WCl₆-based catalysts for the present polymerization. The polymer yield increased in the following order: H > OMe > CN, according to substitutents. The [poly-(pheny] propargyl ether) [poly(PPE)] and poly(methoxy phenyl propargyl ether) [poly(OMe-PPE)] obtained are completely soluble in various organic solvents such as chloroform, methylene chloride, THF, and 1,4-dioxane. However, poly(cyanophenyl propargyl ether) [poly(CN-PPE)] is partially soluble in various organic solvents such as those mentioned above. The electrical conductivities of the undoped and iodine-doped polymers and found to be about 10^?13 and 10^?4-10^?5 S/cm, respectively. The solubilities, thermal properties, and morphologies of the resulting polymers were also studied.     

Cyclopolymerization of dipropargyl isopropylidene malonate and characterization of the product

The polymerization of dipropargyl isopropylidene malonate (DPIPM) was polymerized by WCl₆ and MoCl₅ associated with various organometallic cocatalysts. MoCl₅ was found to be the most effective catalyst and Ph₄Sn was observed to have a high cocatalyst activity. Structure and physical properties of poly(DPIPM) were investigated. The spectral data indicated that poly(DPIPM) contains alternating double and single bonds along the polymer backbone and a cyclic recurring unit. The poly(DPIPM) was partially soluble in common organic solvents. The M?_n values of the polymer from soluble fraction were in the range of 5100–8000 relative to polystyrene standards by GPC. In addition, poly(DPIPM) possesses good stability to air oxidition. When poly(DPIPM) is exposed to iodine vapor, the electrical conductivity was increased from 4.5 × 10^?11 to 7 × 10^?2 S/cm. © 1993 John Wiley & Sons, Inc.     

Pd/羧基功能化离子液体选择性催化氧化苯乙烯

 利用羧基对咪唑型离子液体的阳离子进行功能化,得到一系列具有不同羧基数目及与不同阴离子搭配的N-羧基功能化咪唑离子液体(TSILs), 进而构筑PdCl2/TSILs催化剂体系. 以过氧化氢为氧化剂,将PdCl2/TSILs用于选择性催化氧化苯乙烯合成苯乙酮. 研究结果表明, PdCl2/TSILs催化体系对目标反应具有理想的催化性能,羧基功能化离子液体的阳离子及其搭配的阴离子对苯乙酮的选择性和产率均有显著的影响. 阳离子的羧基数目越多,阳离子的不对称性越高, PdCl2/TSILs催化剂体系的活性越好. 含有相同阳离子的PdCl2/TSILs催化剂体系,其催化性能按照阴离子PF-6＜H2PO-4＜Cl-＜BF-4的顺序递增且与其酸强度顺序相反. 含有三羧基的功能化离子液体与PdCl2构筑的催化剂体系具有最佳的催化性能,在55 ℃下,该催化剂体系的转换频率值达到125 h-1, 苯乙烯可以完全转化且苯乙酮的选择性为91%.     

Synthesis and structure of palladium complexes [Ph3PhCH2P]+[PdCl3(DMSO)]− · DMSO, [Ph4P]+[PdCl3(DMSO)]−, and [Ph4Sb(DMSO)]+[PdCl3(DMSO)]−

[Ph₃PhCH₂P]⁺[PdCl₃(DMSO)]^? · DMSO (I), [Ph₄P]⁺[PdCl₃(DMSO)]^? (II), and [Ph₄Sb(DMSO)]⁺[PdCl₃(DMSO)]^? (III) complexes have been synthesized via the reaction of palladium chloride with equimolar amounts of triphenylbenzylphosphonium chloride, tetraphenylphosphonium chloride, and tetraphenylstibonium chloride, respectively. According to X-ray diffraction data, the cations of complexes I (CPC = 104.90(8)°–111.61(9)°) and II (CPC = 105.12(10)°–111.46(10)°) have slightly distorted tetrahedral structures with P-C bond lengths of 1.786(2)–1.809(2) and 1.791(2)–1.799(2) Å, respectively. The antimony atom in the [Ph₄Sb(DMSO)]⁺ cation has a trigonal bipyramidal surrounding with the dimethyl sulfoxide (DMSO) oxygen atom in an axial position (Sb...O 2.567(2) Å). The palladium atoms in the square mononuclear anions of complexes I, II, and III are tetracoordinate, and Pd-Cl distances are 2.3101(5)–2.3104(5) Å, 2.2950(7)–2.2038(7) Å, and 2.2986(9)–2.3073(9) Å, respectively. The DMSO ligands are coordinated to the palladium atom through the sulfur atom (Pd-S, 2.2318(5) (I), 2.2383(6) (II), and 2.2410(9) Å (III)).     

Competing reactions of hydrophenylation and phenylation in tetraphenylantimony chloride methyl acrylate palladium chloride system

A new catalytic reaction of the competing phenylation and hydrophenylation in air of methyl acrylate with tetraphenylantimony chloride in the presence of PdCl₂ (0.04 mol per 1 mol of organometallic compound) in acetonitrile at 50°C for 6 h was studied. The yields of methyl cynnamate and methyl hydrocynnamate were 0.73 and 0.27 mol mol^?1 respectively. The products ratio obtained depends slightly on the process duration, the Ph₄SbCl and methyl acrylate ratio, and the structure of Pd salt [PdCl₂, Pd(OAc)₂, Li₂PdCl₄], but significantly on the nature of a solvent (MeCN > DMF > THF). The use of Ph₄SbCl instead of Ph₄SbBr leads to decrease in the yield of methyl hydrocynnamate to 0.04 mol mol^?1. In the reactions of Ph₄SbX (X = F, I, OAc, O₂CEt) the product is not formed at all.     

Studies on Synthesis and Effect of Dopants on Conductivity and Morphology of Organically Soluble Poly(o-anisidine)

Synthesis of poly(o-anisidine) doped with various protonic acids by using ammonium persulphate as oxidizing agent were carried out in aqueous acid media. Influences of protonic acids on the physicochemical properties were investigated. The various process parameters were optimized to obtain poly(o-anisidine) in the conducting salt phase form. The results are discussed with references to different protonic acids. It was observed that poly(o-anisidine) is highly soluble in organic solvents, such as m-cresol and N-methyl pyrrolidinone (NMP). The polymers were characterized by UV-Visible, FTIR, SEM, XRD and conductivity measurements. A result shows that, different types of dopant acids HCl, H₂SO₄ and HClO₄ affect the morphology and electrical conductivity of the polymer. The electrical conductivity of the polymer follows the order HCl >H₂SO₄>HClO₄. Thus the effect of dopant ion type and the size of its negative ions influence the physico-chemical properties. UV-Vis absorption spectra shows peaks at 740–783 nm with shoulder at 380–420 nm as characteristic peaks for the emeraldine salt (ES) phase of poly(o-anisidine) POA. The FTIR spectra show a broad and intense band at ～2800–3001 cm^?1 and ～1159–1170 cm^?1 that account for the formation of ES phase of the polymer. The X-ray diffraction spectra show a characteristic peak at 20–30^o, 2θ range which reveals partial crystalline structure. The conductivity of the poly(o-anisidne) salt was found to be in the range of 10^?3 to 10^?2 S/cm. SEM studies of poly(o-anisidine) doped with HCl shows the continuous granular uniform morphology with sub-micrometer evenly distributed particles of size ～100–200 nm.     

Polymerization of 1-Ethynyl-1-Cyclohexanol by Transition Metal Catalysts

Abstract

The polymerization of 1-ethynyl-l-cyclohexanol (ECHO) was carried out by various transition metal catalysts. The Mo- and W-based catalysts gave a relatively low yield of polymer (≤32%). The catalytic activity of Mo-based catalysts was greater than that of W-based catalysts. PdCl₂ was a very effective catalyst for the present polymerization and gave a high yield of polymer. (Ph₃P)₂PdCl₂ and PtCl₂ were also found to be effective catalysts. The structure of the resulting poly(ECHO) was identified by various instrumental methods as a conjugated polyene structure having an α-hydroxycyclohexyl substituent. The poly(ECHO)s were mostly light-brown powders and completely soluble in various organic solvents such as chloroform, chlorobenzene, benzene, DMSO, and THF. Thermal and morphological properties were also studied.     

Ultrasonic Solution Degradations of Poly(Alkyl Methacrylates)

Ultrasonic (70 W, 20 kHz) solution (2%) degradations of poly(alkyl methacrylates) have been carried out in toluene at 27°C and in tetrahydrofuran (THF) at -20°C. M_w and M_n of all polymers (before and after sonification) were computed from GPC. Irrespective of the alkyl substituent, M_w decreased rapidly at first and then slowly approached limiting values. All M_w/M_n ratios were in the vicinity of 1.5 at the limiting chain lengths. For identical M_n, the rate constants k were (4.2 ± 2.0) × 10^?6 min^?1 in toluene at 27°C and (5.4 ± 2.0) × 10^?6 min^?1 in THF at -20°C. For poly(isopropyl methacrylate) and poly(octadecyl methacrylate) with higher, but identical, M_n,0, k values were higher ((9.0 ± 1.0) × 10^?6 min^?1 at 27°C and (18.0 ± 1.5) × 10^?6 min^?1 at -20°C). This suggests that M_n,0 and not the bulk size of the alkyl substituents is the factor that determines the rate of degradation. Lowering of the temperature accelerates degradation due primarily to lower chain mobility of poly-(alkyl methacrylates) and enhanced cavitation. The average number of chain scissions ([(M_n)₀/(M_n)_t] - 1) calculated from component degradation data are much higher than those obtained with overall M_n,t values.     

Trichloropalladate(II) Complexes with Pyridine Ligands – Molecular Structure and Conformational Analysis of [K(18C6)][PdCl3(py)]

[K(18C6)]₂[Pd₂Cl₆] ( 1 ) (18C6 = 18‐crown‐6) was found to react with pyridines in a strictly stoichiometric ratio 1 : 2 in methylene chloride or nitromethane to yield trichloropalladate(II) complexes [K(18C6)][PdCl₃(py*)] (py* = py, 2a ; 4‐Bnpy, 2b ; 4‐tBupy, 2c ; Bn = benzyl; tBu = tert‐butyl). The reaction of 1 with pyrimidine (pyrm) in a 1 : 1 ratio led to the formation of the pyrimidine‐bridged bis(trichloropalladate) complex [K(18C6)]₂[(PdCl₃)₂(μ‐pyrm)] ( 3 ). The identities of the complexes were confirmed by means of NMR spectroscopy (¹H, ¹³C) and microanalysis. The X‐ray structure analysis of 2a reveals square‐planar coordination of the Pd atom in the [PdCl₃(py)]^? anion. The pyridine plane forms with the complex plane an angle of 55.8(2)°. In the [K(18C6)]⁺ cation the K⁺ lies outside the mean plane of the crown ether (defined by the 6 O atoms) by 0.816(1) Å. There are tight K···Cl contacts between the cation and the anion (K···Cl1 3.340(2) Å, K···Cl2 3.166(2) Å). To gain an insight into the conformation of the [PdCl₃(py)]^? anion, DFT calculations were performed showing that the equilibrium structure ( 6eq ) has an angle between the pyridine ligand and the complex plane of 35.3°. Rotation of the pyridine ligand around the Pd–N vector exhibited two transition states where the pyridine ligand lies either in the complex plane ( 6TS _pla, 0.87 kcal/mol above 6eq ) or is perpendicular to it ( 6TS _per, 3.76 kcal/mol above 6eq ). Based on an energy decomposition analysis the conformation of the anion is discussed in terms of repulsive steric interactions and of stabilizing σ and π orbital interactions between the PdCl₃^? moiety and the pyridine ligand.     

On the thermal decomposition of K2PdCl4 in a hydrogen atmosphere

The decomposition of single crystals and powders of K₂PdCl₄ in a hydrogen atmosphere was investigated by means of thermogravimetry (TG) at temperatures between 85 and 170°C, and by optical microscopy. The rate of decomposition is controlled by a combined process of nucleation and growth. The activation energy was calculated to be 15.2 ± 0.5 kcal mol^?1 for single crystals and 13.5 ± 0.4 kcal mol^?1 for powders. The results are compared with those obtained for K₂PtCl₄.An attempt was made to explain the differences in the orientation relationships, previously determined by X-ray diffraction, between K₂PtCl₄ and K₂PdCl₄, Rb₂PdCl₄ and K₂PdBr₄ and their decomposition products with a different kinetic behaviour.     

Synthesis,Crystal Structure,Spectral and Thermodynamic Properties of One Benzoindole Pentamethine Cyanine Dye

One benzoindole pentamethine cyanine dye was synthesized and characterized by ¹H NMR, IR, MS and UV‐Vis spectra. The UV‐Vis absorption and fluorescence spectra of the dye in chloroform, dimethyl sulfoxide, acetone, ethanol and methanol were investigated, and the λ_max of the dye was in the region 682.0–689.0 nm with large molar extinction coefficients (? > 10⁵ M^?1cm^?1) in different solvents. The structure of the dye was also characterized and analyzed by X‐ray diffraction. Crystallographic data revealed that the dye belonged to orthorhombic, with space group P2₁2₁2₁, a = 10.059(2) Å, b = 15.098(4) Å, c = 24.989(6) Å, V = 3794.8(15) ų, Z = 4. The C‐H···F intermolecular hydrogen bonds were displayed in the molecular system, which were effective in the molecular packing. The aggregation behavior and thermodynamic properties of the dye in aqueous methanol solution were also studied by means of UV‐Vis spectroscopy methods. The results indicated that the dye existed monomer‐dimer equilibrium in aqueous methanol solutions. The fundamental properties of the dye, such as the dimeric association constant K_D, the dimeric free energy ΔG_D, the dimeric entropy ΔS_D, and the dimeric enthalpy ΔH_D were determined. The ΔH_D of the dye was –46.0 kJ mol^?1.     

Structure and inclusion property of supramolecular host framework [H2 L1][XCl4], L1 = N,N,N′,N′-tetra-p-methoxybenzyl-ethylenediamine; X = Fe, Co, Pd

In this paper, we have used the hydrogen-bonding interactions, combining the designed diamine ligands and anionic metal chlorides, into the construction of a series of new pillar-layered supramolecular complexes. The flexible molecule N,N,N′,N′-tetra-p-methoxybenzyl-ethylenediamine (L1) bearing doubly protonated H-bond donors, has been synthesized and reacted with the metal chlorides (such as [PdCl₄]^2?, [FeCl₄]^? and [CoCl₄]^2?) via weak C–H···Cl interactions, yielding crystal products [H₂ L1]²⁺·Cl^?·[FeCl₄]^? (1), 0.5H₂O ? [H₂ L1]²⁺·Cl^?·0.5[PdCl₄]^2? (2) and [2-hydroxy naphthyl]_1.5 ? 2[H₂ L1]²⁺·2Cl^?·[CoCl₄]^2? (3). The 3-D networks are organic double layers formed by the self-assembly of the ligands through extensive hydrogen-bonding interactions (C–H···O or C–H···π interactions) and further interconnected by [PdCl₄]^2?/[FeCl₄]^?/[CoCl₄]^2? in a pillar fashion, constructing into pillar-layered networks with channels accessible to various guest molecules. The inclusion property of [H₂ L1][CoCl₄] was studied, varieties of guest molecules, such as 2-hydroxy naphthyl, phenanthrene and hydroquinone, can be included in the framework.     

Casting of poly (vinyl alcohol)/glycidyl methacrylate reinforced with titanium dioxide nanoparticles for proton exchange fuel cells

Gamma irradiation was used for cross-linking poly (vinyl alcohol) (PVA) and glycidyl methacrylate (GMA) mixtures of different compositions. Specifically, 0.5 wt% titanium dioxide (TiO₂) nanoparticles were added and blended well with the casting mixture prior to exposure to the irradiation dose. Next, 10 kGy was found to be the optimum dose for achieving the desired physical and chemical properties of the membrane. Characterizations of the cast membranes were carried out by Fourier transformer infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and positron annihilation lifetime spectroscopy (PALS). The properties of the membrane were also characterized by ion exchange capacity (IEC), water uptake, and tensile strength and were assessed in relation to application in proton exchange membrane fuel cells (PEMFCs). A maximum proton conductivity of 7.3 × 10^?2 S cm^?1 was obtained for the membrane having 20 % GMA, 80 % PVA, and 0.5 % TiO₂, and its activity and durability in a membrane electrode assembly (MEA) were compared to those of a commercial Nafion® 1350.     

Synthesis and Characterization of Palladium(II) Complexes with 2‐(2′‐Pyridyl)quinoline. Catalytic Air Oxidation of Olefins by Palladium(II) Complexes

Palladium(II) complexes of 2‐(2′‐pyridyl)quinoline (PQ), namely [PdX₂(PQ)] (X = Br^?, I^?, N₃^?, NO₂^?, SCN^?, acac) and [PdCl(NO₃)(PQ)] have been synthesized via substitution reactions of [PdCl₂(PQ)] with an excess of sodium salts and acetylacetone. The complexes have been characterized by elemental analysis, conductivity measurements, IR, ¹H and ¹³C NMR spectroscopy. Selected complexes have been further characterized using electrospray ionization (ESI) and ion trap mass spectroscopy (ITMS). Some complexes are found to catalyze the rapid air oxidation of α‐olefins under Wacker oxidation. The chlorohydrin products are produced in good to excellent yields while oxidation products are obtained in low yields. The [PdCl₂(PQ)] complex is found to have the highest catalytic activity.     

Preparation,characterization, and evaluation of LiNi0.4Co0.6O2 nanofibers for supercapacitor applications

We prepared LiNi_0.4Co_0.6O₂ nanofibers by electrospinning at the calcination temperature of 450 °C for 6 h. The prepared LiNi_0.4Co_0.6O₂ nanofibers was characterized by thermal, X-ray diffraction, and Fourier transform infrared (FTIR) studies. The morphology of LiNi_0.4Co_0.6O₂ nanofibers was characterized by scanning electron microscopy studies. The asymmetric supercapacitor was fabricated using LiNi_0.4Co_0.6O₂ nanofibers as positive electrode and activated carbon (AC) as negative electrode and a porous polypropylene separator in 1 M LiPF₆–ethylene carbonate/dimethyl carbonate (LiPF₆–EC:DMC) (1:1?v/v) as electrolyte. Cyclic voltammetry studies were then carried out in the potential range of 0 to 3.0 V at different scan rates which exhibited the highest specific capacitance of 72.9 F g^?1. The electrochemical impedance measurements were carried out to find the charge transfer resistance and specific capacitance of the cell, and they were found to be 5.05 Ω and 67.4 F g^?1, respectively. Finally, the charge–discharge studies were carried out at a current density of 1 mA cm^?2 to find out the discharge-specific capacitance, energy density, and power density of the capacitor cell, and they were found to be 70.9 F g^?1, 180.2 Wh kg^?1, and 248.0 W kg^?1, respectively.     

Highly selective probe of a copper(II) complex based on a coumarin derivative for hydrogen sulfide detection

Abstract

A fluorescent probe 1 containing copper(II) had been designed and synthesized based on a coumarin derivative. The molecular structure of probe 1 was characterized by ¹H NMR, HRMS, IR, and elemental analysis. The interactions of 1 with biologically important anions and amino acid were determined by UV–Vis, fluorescence, and HRMS titration experiments. Results indicated that probe 1 showed the highest binding ability for HS^? among studied anions (AcO^?, H₂PO₄^?, F^?, Cl^?, Br^?, and I^?) and cysteine in pure dimethyl sulfoxide (DMSO) and HEPES buffer solution. As we expected, the response of UV–Vis spectra in aqueous solution was stronger than that of pure DMSO solvent. In addition, the binding ability for HS^? was not hindered by the existence of other anions. HRMS titration experiment showed that the interacted mechanism was that the copper(II) ion in 1 was captured by HS^? and then free ligand released. Furthermore, the detection limit of probe 1 with HS^? was carried out through UV–Vis titration showing 1 to be highly sensitive for HS^?.     

Rate constants for the reactions of chlorine atoms with hydrochloroethers at 298 k and atmospheric pressure

The relative rate technique has been used to determine the rate constants for the reactions Cl + CH₃OCHCl₂ → products and Cl + CH₃OCH₂CH₂Cl → products. Experiments were carried out at 298 ± 2 K and atmospheric pressure using nitrogen as the bath gas. The decay rates of the organic species were measured relative to those of 1,2‐dichloroethane, acetone, and ethane. Using rate constants of (1.3 ± 0.2) × 10^?12 cm³ molecule^?1 s^?1, (2.4 ± 0.4) × 10^?12 cm³ molecule^?1 s^?1, and (5.9 ± 0.6) × 10^?11 cm³ molecule^?1 s^?1 for the reactions of Cl atoms with 1,2‐dichloroethane, acetone, and ethane respectively, the following rate coefficients were derived for the reaction of Cl atoms (in units of cm³ molecule^?1 s^?1) with CH₃OCHCl₂, k= (1.04 ± 0.30) × 10^?12 and CH₃OCH₂CH₂Cl, k= (1.11 ± 0.20) × 10^?10. Errors quoted represent two σ, and include the errors due to the uncertainties in the rate constants used to place our relative measurements on an absolute basis. The rate constants obtained are compared with previous literature data and used to estimate the atmospheric lifetimes for the studied ethers. © 2005 Wiley Periodicals, Inc. Int J Chem Kinet 37: 420–426, 2005     

Synthesis and crystal structure of the salt of the protonated thiamine cation with the palladium(II) tetrachloride anion [HTA]2[PdCl4]Cl2 · 2H2O

The reaction of thiamine chloride hydrochloride with a solution of palladium chloride in hydrochloric acid gave a protonated thiamine salt [HTA]₂[PdCl₄]Cl₂ · 2H₂O (I) (TA is 4-methyl-3-[(2??-methyl-4??-amino-3??,4??-dihydropyrimidinyl-5??)methyl]-5-(2-hydroxyethyl)thiazolium cation, C₁₂H₁₆N₃O₂S). The crystal structure of I was determined by X-ray diffraction. The crystals are triclinic: a = 11.459(8) ?, b = 12.239(8) ?, c = 6.910(1) ?, ?? = 103.24(3)°, ?? = 76.95(3)°, ?? = 106.04(3)°, Z = 2, space group P $\bar 1$ . The structural units of I are doubly charged [HTA]²⁺ cations, [PdCl₄]^2? and Cl^? anions, and crystallization water molecules combined by hydrogen bonds and electrostatic interactions. The planar thiazolium and pyrimidine rings are in the F conformation, ??_t = 1.0°, ??_p = ?86.6°, and the dihedral angle between the planes is 85.5°. The torsion angles of the hydroxyethyl group are as follows: C(9)C(10)C(11)O(1), 175.6°; S(1)C(9)C(10)C(11), 33.2°; it is involved in the hydrogen bond with the free Cl^? anion. The sulfur atom forms a short (3.052 ?) intermolecular S-Cl contact with the chlorine atom of the [PdCl₄]^2? anion, which forms supramolecular chains.     

EQUILIBRIUM STUDIES OF THE REACTION BETWEEN TETRACHLOROPALLADIUM(II) ANION AND SULFOXIDES. THE FORMATION OF THE MONO-S-SULFOXIDE COMPLEXES

Abstract

The equilibrium coefficient, K₁, for the reaction [PdCl₄]^2- + RR′ SO ? [Pd(RR′ SO)Cl]^? + Cl^?, has been determined for dimethylsulfoxide, tetramethylensulfoxide, and phenylmethylsulfoxide and found to be 67, 46 and 8.8 respectively at 25°C, ü= 1.0 in 95:5 methanol-water. Values for the equilibrium constants for the dimethylsulfoxide complex are also reported at other ionic strengths. The equilibrium constants for the second stage, [Pd(Me₂SO)Cl₃]- + Me₂SO)?-[Pd(Me₂SO)₂Cl₂] + Cl^?, has been determined for dimethylsulfoxide only, K₂=2.5 × 10^?2 at 25°C (μ not controlled). The causes of the mutual destabilisation of two dimethylsulfoxides are discussed.     

Behavior of aqueous solutions of polymer star with block copolymer poly(2-ethyl-2-oxazoline) and poly(2-isopropyl-2-oxazoline) arms

Eight-arm star-shaped poly(2-alkyl-2-oxazoline) (M?≈?21,000?g?·?mol^?1) was studied by turbidimetry and light scattering in aqueous solutions within concentration ranging from 0.00038 to 0.0276?g?·?cm^?3. The arms were the block copolymers of poly(2-isopropyl-2-oxazoline) (PiPrOx) and poly(2-ethyl-2-oxazoline) (PEtOx). Calix[8]arene core was connected with poly(2-isopropyl-2-oxazoline). The behavior of investigated polymer differed from that of thermosensitive stars with poly(2-alkyl-2-oxazoline) homopolymer arms. At low temperatures, the aggregates were formed due to interaction of hydrophobic cores. The phase separation temperatures T₁ and T₂ of studied star were higher than those for star-shaped poly(2-isopropyl-2-oxazoline) and lower than for poly(2-ethyl-2-oxazoline). T₁ and T₂ increased with dilution.