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Understanding the “real” structure of a nucleating agent (NA) inducing polymer crystallization is the basis for establishing the structure–nucleation performance relationship. N,N′-Dicyclohexyltere...

In this contribution, novel bio-derived rosin acid ester compounds have been developed and used as internal electron donors to prepare MgCl2 supported titanium catalysts for propylene polymerization. The results of the polymerization showed that tri-n-amyl maleate, triiso-amyl maleate and tri-n-heptyl maleate as internal electron donors in Ziegler-Natta catalysts all have high polymerization activity and stereoregularity. In particular, the Ziegler-Natta catalyst with tri-n-amyl maleate as the internal electron donor has the highest activity (up to 33.4 kgPP·gCat−1·h−1) for propylene polymerization and the isotacticity of polypropylene is as high as 96.8% determined by 13C NMR. Simultaneously, the obtained polypropylene with a relatively broad molecular weight distribution of 9.0 and melt flow rate of 160.3 g/10 min, which is beneficial to processing and has practical industrial application value when used as the basic material of melt blown cloth for medical mask.

The preparation method of nano-scaled polymeric materials was described in this work. Nano-scaled novel composites of elastomeric ter-polypropylene blended with isotactic polypropylene (iPP) were investigated. The composites were synthesized by zirconium complex/methylaluminoxane(MAO) catalyst system through in-situ polymerization. This novel materials consisted of different lengths of crystallizable iPP segments and rubbery amorphous blocks that polymerized by 1-octene, propylene and ethylene in varying proportions. The mechanical properties of the composites were desired that the iPP segments contributed to the strength and the rubbery amorphous blocks contributed to the flexibility. The result showed that the composites can be used as a kind of elastomer.

In the present work, the synergistic toughening effect of olefin block copolymer (OBC) and a highly effective β nucleating agent (NA)-Calcium salt of pimelic acid (CaPim) on polypropylene random copolymer (PPR) was studied. Mechanical tests showed that with the introduction of 0.1 wt % CaPim, there was almost no change in the low-temperature (below 0 °C) toughness of PPR. Although introduction of OBC could obviously improve the toughness at 23 °C, high content is needed to effectively toughen PPR at low temperature. By coadding OBC and CaPim, PPR/OBC/NA blends showed not only great enhancement of toughness over the temperature range tested but also lower OBC content of undergoing brittle-ductile transition compared with PPR/OBC blends. The crystalline structure, crystallization behavior and phase morphology were investigated to explore the possible synergistic toughening mechanism. The high β-crystal content formed in PPR matrix and the finer distribution of OBC phase might be responsible for the superior...

The incorporation of fluorine into polyolefin can dramatically improve its own mechanical properties and compatibility with other polymers, which has revolutionized the development of polyolefin industry. However, there were no fluorinated isotactic polypropylene (iPP) on the market which remains a formidable challenge. Here, a novel approach is presented that fluorinated iPP was prepared by free radical reaction using N-fluorobenzenesulfonimide (NFSI) as fluorine transfer reagent and benzoyl peroxide (BPO) as initiator in solution reaction. By conducting the tests of water contact angle (CA), DSC and TGA, the results indicated that the surface property and the thermal stability of fluorinated iPP (F-iPP) were greatly improved. In this contribution, a direct and economical route to fluorinate polyolefin was provided.

The memory effect of semi-crystalline polymers is usually related to the heterogeneity in self-nucleated (SN) melts. In this study, the strong memory effects of syndiotactic polypropylene (sPP) and the heterogeneity in SN melts were systematically investigated in a wide temperature range even above its equilibrium melting temperature (Tmo). The rheological measurements revealed that the SN melts exhibited thermorheologically complex behaviors, indicating that the presence of the heterogeneity in the SN melts. From the rheological plots of phase angle (δ) with the complex modulus (G*), the parameter Δ ln G* δ=45° values were determined and used to compare the change of the degree of thermorheological complexity in the SN melts during the heating process. It was found that the memory effect's efficiency to promote the crystallization process improved as the increase of Δ ln G* δ=45° values, which suggested that the memory effect depended on the heterogeneity in the SN melts. After purifying the sample, the strong memory effect still existed, which indicated that it was not caused by the stabilization effect of impurities. The results of wide/small-angle X-ray scattering and infrared spectroscopy revealed that there were no partial residual crystallites or regular chain conformation in our investigated SN melts. Based on the complex chain structure of our investigated sPP, we speculated that the heterogeneity in sPP melts was caused by the separation between the long crystallizable sequence and the atactic sequence.

In this work, the toughening effect of olefin block copolymer (OBC) on polypropylene random copolymer (PPR) at room and low temperature (0 °C) was investigated. Mechanical tests showed that OBC is an effective impact modifier for PPR. By addition of only 5 wt% of OBC, the notched Izod impact strength of resulting blends at room temperature and 0 °C are 66.5, 9.27 kJ/m2, which are increased 135.8 and 43.9%, respectively. This value for blends containing 10 wt% OBC at 0 °C is 60.2 kJ/m2, which is approximately eight times higher than that of pristine PPR at same temperature. Due to the high melting point of OBC, the decline of rigidity caused by its addition is rather slight. The tensile strength and flexural modulus for blends containing 10 wt% OBC is only 8.3 and 11.3% lower than that of pristine PPR. The investigation of morphology, crystallization and rheological behaviors suggested that the great improvement of toughness might be attributed to the decrease of PPR spherulites size and the excellent compatibility between PPR matrix and OBC dispersed phase. This work offers a simple and effective approach to produce PPR with stiffness–toughness balance. Keywords: Polypropylene random copolymer, Olefin block copolymer, Mechanical properties, Stiffness–toughness balance

A series of heterogeneous catalysts by loading metallocenes on surface of α-Ti(HPO4)2, a kind of solid acid, has been synthesized. Polymerization of alkenes, including ethylene and propylene, based on participation of the heterogeneous catalysts were studied and the results were compared to metallocenes supported on silica gel, α-Zr(HPO4)2 and clay. Higher catalytic activity, larger polymer molecular weight and narrow distribution of polymer molecular weight were obtained. Acidic strength of the support and its influence to metallocenes were studied to discover intrinsic factors in the polymerizations.

The example of the preparation of nano- and micro-scaled, coral-shaped and core-shell topological morphology of copolyethylene particles promoted by the novel heterogeneous non-metallocene catalyst (m-CH3PhO)TiCl3/carbon nanotubes (CNTs) was reported. Mass fraction of titanium component of the catalyst was 4.0 wt% determined by ICP analysis. The catalyst system can effectively catalyze polymerization of ethylene and copolymerization of ethylene with 1-hexene. Morphological examination of the obtained polymer particles was carried out by scanning electron microscope (SEM) and high resolution transmission electron microscope (HR-TEM) technique. The results revealed that the morphology of the nascent copolyethylene particles looked like coral shape with size in micro-scaled and featured the core-shell structure consisting of CNTs as the core and copolyethylene as the shell.

A series of titanium and zirconium complexes with ligands based on di-isopropyl phosphorus-phenylamine and their derivatives were synthesized and characterized. These catalysts were utilized to catalyze the copolymerization of ethylene with N-acetyl-O-(dec-9-enyl)-L-tyrosine ethyl ester with high catalytic activity of 6.63 × 104 g P (mol Ti)−1 h−1 after activation by methylaluminoxane (MAO). The effects of ligand structure, metal atoms (Ti, Zr) and polymerization conditions were investigated in detail. The obtained polymers were characterized by 13C-NMR, DSC, FT-IR, and GPC. The results showed that the obtained copolymer had a high comonomer incorporation rate of 2.56 mol % within the copolymer chain. The melting temperature of the copolymer was up to 138.9 °C, higher than that of the obtained homopolyethylene.

The series of acenaphthylene-1-[2,6-bis(bis(4-fluorophenyl)methyl)-4-methylphenylimino]-2-arylimine derivatives and their dichloronickel complexes were synthesized and fully characterized as well as the single-crystal X-ray diffraction of representative nickel complexes, revealing a distorted tetrahedral geometry. Upon activation with either MAO or Et2AlCl, all nickel complexes showed high activities in ethylene polymerization; moreover, their catalytic systems showed better thermal stabilities on being manipulated at 80 °C as the industrial operating temperature.

Preparation of novel polyethylene/carbon nanotubes (CNTs) nanocomposites with core–shell structure was presented. The method involved in situ ethylene polymerization in which nanotube surface was treated with Grignard Agent, followed by reacting with active transition metal compound, TiCl 4 . The multiwalled carbon nanotubes (MWCNTs) supported catalysts polymerize ethylene to form polymer nanocomposite. MWCNTs were homogeneously dispersed within polymer matrix, and as expected, the resultant nanocomposites featured core–shell structure which was confirmed by HRTEM. For the nanocomposite, the microscopic examination of the cryogenically fractured surface not only ensured a good distribution of carbon nano-particles in the PE matrix but also revealed the ductile-like fracture. The Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) were employed for the study of covalent sidewall functionalization and chemical bonding environment of MWCNTs, also indicated effective immobilization of titanium catalyst on the MWCNTs surface. The crystalline properties, dielectric property and thermal stability of the nanocomposites were determined by WAXD, impedance analyzer and TGA. The dielectric result showed a slight decline of the dielectric constant of the nanocomposites with increase of the polymerization time, and lower dielectric loss was also observed.

A novel type of nano template was prepared by loading a Ziegler–Natta catalyst on nanosized carbon spheres for ethylene polymerization to form nanosized polyethylene (PE) particles; triethylaluminu...

The effects of introduction of high density polyethylene (HDPE) and further annealing treatment on the toughness of isotactic polypropylene (PP) were systemically investigated. The introduction of HDPE can improve the toughness of PP at no expense of the stiffness. For the PP containing 10 wt% of HDPE, the notched Izod impact strength is increased by approximately 16.3%. After annealed at 130 °C for 12 h, the impact strength of PP alone is increased by 336.7% compared to pristine PP, while this value is dramatically increased by 1107% for the PP containing 10 wt% of HDPE, which suggests that the introduction of HDPE and further annealing treatment have significant synergistic effect on the toughness improvement of PP. Characterization of microstructure evolution of PP with and without HDPE upon annealing reveals that the dramatic improvement in toughness of PP may be attributed to at least three aspects: (1) the prominently reduced spherulite size of PP induced by the introduction of HDPE, (2) the changes of crystallinity and molecular mobility upon the annealing treatment, which would promote the cavitation process during deformation, and (3) the enhanced interface in PP/HDPE blend upon the annealing treatment.

Two novel cycloalkoxy silane compounds (ED1 and ED2) were synthesized and used as the external electron donors (EEDs) in Ziegler–Natta catalysts with diethyl 2,3-diisopropylsuccinate as internal electron donor. The results indicated that the Ziegler–Natta catalysts using ED1 and ED2 as EEDs had high catalytic activities and good stereoselectivities. The melt flow rate (MFR) and gel permeation chromatography (GPC) results revealed that the obtained polypropylene has higher MFR and lower average molecular weights than the commercial EED cyclohexyl methyl dimethoxysilane. The differential scanning calorimetry (DSC) results indicated that new isospecific active centers formed after the introduction of new external donors. The work implied that the novel EEDs could improve the hydrogen sensitivities of the catalyst system and obtain polymers with high melt flow rate.

A new method was presented for preparing (co-)polyethylene with broad molecular weight distribution (MWD) and high molecular weight employed by the novel heterogeneous Ziegler–Natta catalysts via one-pot strategy. The preparation of these catalysts involved the introduction of alkoxy silane compounds as electron donors. The influences of the electron donors structure, as well as polymerization conditions such as temperature, molar ratio of Al/Ti, ethylene pressure and the concentration of 1-hexene in feed on the polymerization performance for ethylene (co-)polymerization, were investigated. The morphology of the catalyst particles was characterized by SEM and Ti content of these catalysts was characterized by ICP. The GPC results showed that the obtained homopolyethylene and ethylene/1-hexene copolymer had the widest molecular weight distribution up to ca 50 when diethoxy-isopropoxy-(t–butoxy)-silane (ED3) was used as internal electron donor. The 13 C NMR and FT-IR analysis indicated that these catalysts efficiently catalyzed the copolymerization of ethylene with 1-hexene.

Phthaldialdehyde and phthaldiketone were treated with substituted phenols of 2-amino-4-methylphenol, 2-amino-5-methylphenol and 2-amino-4-t-butylphenol, respectively, and then treated with transition metal halides of TiCl4, ZrCl4 and YCl3. A series of novel non-metallocene catalysts (1–12) with phenoxy-imine ligands was obtained. The structures and properties of the catalysts were characterized by 1H NMR and elemental analysis. The catalysts (1–12) were used to promote ethylene (co-)polymerization after activation by methylaluminoxane. The effects of the structures and center atoms (Ti, Zr and Y) of these catalysts, polymerization temperature, Al/M (M = Ti, Zr and Y) molar ratio, concentration of the catalysts and solvents on the polymerization performance were investigated. The results showed that the catalysts were favorable for ethylene homopolymerization and copolymerization of ethylene with 1-hexene. Catalyst 10 is most favorable for catalyzing ethylene homopolymerization and copolymerization of ethylene with 1-hexene, with catalytic activity up to 2.93 × 106 gPE (mol Y)−1 h−1 for polyethylene (PE) and 2.96 × 106 gPE (mol Y)−1 h−1 for copolymerization of ethylene with 1-hexene under the following conditions: polymerization temperature 50 °C, Al/Y molar ratio 300, concentration of catalyst 1.0 × 10−4 L−1 and toluene as solvent. The structures and properties of the polymers obtained were characterized by Fourier transform infrared spectroscopy, 13C NMR, wide-angle X-ray diffraction, gel permeation chromatography and DSC. The results indicated that the obtained PE catalyzed by 4 had the highest melting point of 134.8 °C and the highest weight-average molecular weight of 7.48 × 105 g mol−1. The copolymer catalyzed by 4 had the highest incorporation of 1-hexene, up to 5.26 mol%, into the copolymer chain. © 2012 Society of Chemical Industry

A series of novel nonmetallocene catalysts with phenoxy-imine ligands was synthesized by the treatment of phthaldialdehyde, substituted phenol with TiCl4, ZrCl4, and YCl3 in THF. The structures and properties of the catalysts were characterized by H NMR and elemental analysis. These catalysts were used for copolymerization of ethylene with acrylonitrile after activated by methylaluminoxane (MAO). The effects of copolymerization temperature, Al/M (M 1⁄4 Ti, Zr, and Y) ratio in mole, concentrations of catalyst and comonomer on the polymerization behaviors were investigated in detail. These results revealed that these catalysts were favorable for copolymerization of ethylene with acrylonitrile. Cat.3 was the most favorable one for the copolymerization of ethylene with acrylonitrile, and the catalytic activity was up to 2.19 10 g PE/mol.Ti.h under the conditions: polymerization temperature of 50 C, Al/Ti molar ratio of 300, catalyst concentration of 1.0 10 mol/L, and toluene as solvent. The resultant polymer was characterized by FTIR, cross-polarization magic angle spinning, C NMR, WAXD, GPC, and DSC. The results confirmed that the obtained copolymer featured high-weight–average molecular weight, narrow molecular weight distribution about 1.61–1.95, and high-acrylonitrile incorporation up to 2.29 mol %. Melting temperature of the copolymer depended on the content of acrylonitrile incorporation within the copolymer chain. VC 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 50: 2068–2074, 2012

Influence of α- and β-nucleation on brittle-ductile transition temperature (BDTT) of impact-resistant polypropylene copolymers (IPCs) and their phase morphologies were comparatively investigated. Impact test showed that the BDTT of β-nucleated IPC (β-IPC) is ∼ 24°C lower than that of α-nucleated one (α-IPC). Structural characterizations including atomic force and scanning electron microscopic observations, small angle X-ray scattering examination, and dynamical mechanical analysis revealed that dispersion of the ethylene-propylene random copolymer-rich (EPR-rich) phase was finer in β-IPC in comparison with that in α-IPC. For the reason of looser lamellar arrangement, the portion of EPR-rich components included in the interlamellar region of β-IPC was higher than those of α-IPC, which led to improved mobility for the amorphous polypropylene chains. It was proposed that the finer distribution of EPR-rich phase, which might result from faster growth rate of the β-crystal and looser lamellar arrangement of β-spherulite, should be responsible for the improved impact-resistance and lower BDTT in β-IPC samples. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

In our previous work [22] , a kind of layered compound of zirconium phosphate–glyphosate (ZrGP) was synthesized. Its large surface area (445 m2/g) indicates this compound has possible application in adsorptions. In this paper, adsorption to formaldehyde in ZrGP and mechanisms of the adsorption were studied carefully. Balance time of adsorption (about 6 h) and largest adsorbed amount (7.8%) were found when adsorption temperature was at 40 °C and pH value of adsorption environment was about 3.0. H-bonds were found existing between molecules of formaldehyde and ZrGP, and formaldehyde molecules could exist in ZrGP stably.

Comparison with the conventional Ziegler–Natta catalyst TiCl4/MgCl2 (I), the modified supported Ziegler–Natta catalysts (iso-PentylO)TiCl3/MgCl2 (II) and (BzO)TiCl3/MgCl2 (III) were prepared as efficient catalysts for copolymerization of ethylene with 1-octene. The complexes (II) and (III) were desirable for the production of random ethylene/1-octene copolymers coupled with higher molecular weight, higher comonomer incorporation within copolymer chain and good yield even at high temperature 80 °C and fairly low Al/Ti molar ratio of 100. The effects of catalysts ligands, Al/Ti molar ratio, polymerization temperature, as well as concentration of 1-octene on the catalytic activity, molecular weight and microstructure of the copolymer were investigated in detail. The structure and properties of the copolymers were characterized with 13C NMR, GPC, DSC and WAXD. The kinetic results also indicate that these catalysts (II) and (III) show higher catalytic activity and the produced polymers feature higher molecular weight, because of lower ratio of Ktrm/Kp and Ktra/Kp, and higher ratio of Ktra/Ktrm which indicates that chain transfer to cocatalyst is predominant.

A series of novel bridged multi-chelated non-metallocene catalysts is synthesized by the treatment of N,N-imidazole, N,N-dimethylimidazole, and N,N-benzimidazole with n-BuLi, 2,6-dimethylaniline, and MCl4 (M = Ti, Zr) in THF. These catalysts are used for copolymerization of ethylene with 1-hexene after activated by methylaluminoxane (MAO). The effects of polymerization temperature, Al/M molar ratio, and pressure of monomer on ethylene copolymerization behaviors are investigated in detail. These results reveal that these catalysts are favorable for copolymerization of ethylene with 1-hexene featured high catalytic activity and high comonomer incorporation. The copolymer is characterized by 13C NMR, WAXD, GPC, and DSC. The results confirm that the obtained copolymer features broad molecular weight distribution (MWD) about 33–35 and high 1-hexene incorporation up to 9.2 mol %, melting temperature of the copolymer depends on the content of 1-hexene incorporation within the copolymer chain and 1-hexene unit in the copolymer chain isolates by ethylene units. The homopolymer of ethylene has broader MWD with 42–46. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 417–424, 2010

A series of N-(2-benzimidazolyquinolin-8-yl)benzamidate half-titanocene chlorides, Cp′TiLCl (C1–C8: Cp′ = C5H5, MeC5H4, or C5Me5; L = N-(benzimidazolyquinolin-8-yl)benzamides)), was synthesized by the KCl elimination reaction of half-titanocene trichlorides with the correspondent potassium N-(2-benzimidazolyquinolin-8-yl)benzamide. These half-titanocene complexes were fully characterized by elemental and NMR analyses, and the molecular structures of complexes C2 and C8 were determined by the single-crystal X-ray diffraction. The high stability of the pentamethylcyclopentadienyl complex (C8) was evident by no decomposing nature of its solution in air for one week. The oxo-bridged dimeric complex (C9) was isolated from the solution of the corresponding cyclopentadienyl complex (C3) solution in air. Complexes C1–C8 exhibited good to high catalytic activities toward ethylene polymerization and ethylene/α-olefin copolymerization in the presence of methylaluminoxane (MAO) cocatalyst. In the typical catalytic system of C1/MAO, the polymerization productivities were enhanced with either elevating reaction temperature or increasing the ratio of MAO to titanium precursor. In general, it was observed that higher the catalytic activity of the catalytic system lower the molecular weight of polyethylene. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3154–3169, 2009

A series of layered compounds of zirconium glyphosate and zirconium phosphate–glyphosates were synthesized with ZrOCl2, N-(phosphonomethyl)glycine and H3PO4 for the first time. It was found that the morphologies of zirconium phosphate–glyphosates had a strong variational rule from hexagon to sphere and sphere to lamella when n H 3 PO 4 / n Glyphosate changed from ∞ to 0, and also it was found that the product of zirconium glyphosate could be decomposed gradually in basic condition with pH value of lye increased. A monochromatic body of ZrGPEu under illumination of UV light was obtained by Eu3+ exchanged and coordinated with imido and carbonyl groups in the gallery of the layers.

A series of unsymmetric bimetal(II) (Fe, Co and Ni) complexes ligated by 2-methyl-2,4-bis(6-iminopyridin-2-yl)-1H-1,5-benzodiazepines were synthesized and characterized by IR spectra and elemental analysis, while a representative nickel(II) complex (5a) was determined by single-crystal X-ray crystallography. These iron(II) complexes were found to exhibit good activities for ethylene oligomerization and polymerization in the presence of MMAO and afforded α-olefins in high selectivity, and the composition of oligomers followed the Schluz–Flory distribution. The nickel(II) complexes mainly dimerize ethylene with considerable activity. The influences of coordinative ligands and reaction parameters were fully investigated on the catalytic activity and properties of these complexes.

The 1-(6-(quinoxalin-2-yl)pyridin-2-yl)ethanone was synthesized in order to prepare a series of N-(1-(6-(quinoxalin-2-yl)pyridine-2-yl)ethylidene)benzenamines (L1–L7), which provided new alternative N∧N∧N tridentate ligands coordinating with iron(II) and cobalt(II) dichloride to form complexes of general formula LFeCl2 (1–7) and LCoCl2 (8–14). All organic compounds were fully characterized by NMR, IR spectroscopic and elemental analysis along with and magnetic susceptibilities and metal complexes were examined by IR spectroscopic and elemental analysis, while their molecular structures (L1, L4, 1, 4, 10, 13) were confirmed by single crystal X-ray diffraction analysis. Upon activation with methylaluminoxane (MAO), all iron complexes gave good catalytic activities for ethylene reactivity (oligomerization and polymerization), while their cobalt analogues showed moderate activities toward ethylene oligomerization with modified methylaluminoxane (MMAO). Various reaction parameters were investigated for better catalytic activities, the higher activities were observed at elevated ethylene pressure. The iron and cobalt complexes with para-methyl substituents of aryl group linked on imino group showed highest activity.

A kind of macroscopic fiber of α-Zr(C 6 H 5 PO 3 ) 2 with diameter in millimeter scale and length in centimeter is synthesized by the method of infiltration–diffusion in this paper. Compared to the routine method [Q.H. Xu, L.S. Fu, L.S. Li, H.J. Zhang, R.R. Xu, J. Mater. Chem. 10 (2000) 2532], no HF was used in the synthesis and the SEM (scanning electronic microscopy) image indicates that these fibers have tubular structures which composed of flakes overlapped with each other vertically to the growth direction of the fiber. Powder X-ray diffraction (PXRD) proves that the walls of the tubes are composed of α-Zr(C 6 H 5 PO 3 ) 2 (α-ZrBP). As we know, it is the first report on synthesis of fiber-tube to α-ZrBP.

A series of nickel(II) complexes ligated by tridentate ligands of 2-quinoxalinyl-6-iminopyridines was synthesized and characterized by elemental and spectroscopic analysis as well X-ray diffraction analysis. X-ray crystallographic analysis revealed the nickel complexes as five-coordinated distorted trigonal bipyramidal geometry. In the presence of Et 2 AlCl, these complexes displayed high catalytic activity for ethylene oligomerization and the dimmers were produced as main products. The nickel dibromide complexes exhibited relative higher activity than their dichloride analogues. Both elevation of the ethylene pressure and addition of auxiliary ligand have catalytic enhancement effects on all the complexes.

A series of N-acetyl-O-(ω-alkenyl)-l-tyrosine ethyl esters were synthesized by the reaction of vinyl bromides (4-bromo-1-butene, 6-bromo-1-hexene, 8-bromo-1-octene and 10-bromo-1-decene) with N-acetyl-l-tyrosine ethyl ester. 1H NMR, elemental analysis, FT-IR, and mass spectra were performed for these N-acetyl-O-(ω-alkenyl)-l-tyrosine ethyl esters. The novel titanium complex can catalyze the copolymerization of ethylene and N-acetyl-O-(ω-alkenyl)-l-tyrosine ethyl esters efficiently and the highest catalytic activity was up to 6.86 × 104 gP·(molTi)−1·h−1. The structures and properties of the obtained copolymers were characterized by FT-IR, (1H)13C NMR, GPC, DSC, and water contact angle. The results indicated that the obtained copolymers had a uniformly high average molecular weight of 2.85 × 105 g·mol−1 and a high incorporation ratio of N-acetyl-O-(but-3-enyl)-l-tyrosine ethyl ester of 2.65 mol % within the copolymer chain. The units of the comonomer were isolated within the copolymer chains. The insertion of the polar comonomer into a copolymer chain can effectively improve the hydrophilicity of a copolymer.

A kind of nano template catalyst was prepared through loading the active compound (m-CH3PhO)TiCl3 on carbon nanotubes (CNTs). This catalyst can catalyze (co)polymerization of ethylene to form CNTs/polyethylene (PE) nanocomposites particles. The nano template catalyst showed high catalytic activity up to 5.8 kg/(gTi.h.p) for the copolymerization of ethylene with 1-hexene. The results revealed that the nascent CNTs/PE nanocomposites particles looked like coral shape and featured with the core-shell structure which CNTs as the core and polyethylene as the shell.

A diphosphinoamine ligands has been synthesized. In combination with Cr(III), methylalumoxane (MAO) and tetrachloroethane (TCE), they generate active catalytic systems for ethylene tetramerization toward 1-octene. The effects of reaction temperature, reaction pressure, molar ratio of Al/Cr, TCE/Cr, ligand/Cr, reaction time and sorts of cocatalyst on catalytic activity and selectivity to 1-octene were studied. The results show that the diphosphinoamine/Cr(III)/TCE/MAO four-membered catalytic systems for ethylene tetramerization have improved the selectivity to 1-octene, but catalytic activity is lower than that of three component system. MAO is requisite in forming active species for ethylene tetramerization toward 1-octene. TCE shows significant promotion effect to assist chromium center in improving selectivity toward 1-octene.

Reaction of a triangle Pd(0) complex, Pd3(CNXyl)6 (1; Xyl = 2,6-C6H3Me2), with a dicationic linear trinuclear complex [Pd3(CNXyl)8][PF6]2 (3) afforded a dicationic hexapalladium complex [Pd6(CNXyl)12][PF6]2 (4), while the reaction of 1 with a dicationic dinuclear complex [Pd2(CNXyl)6][PF6]2 (2) resulted in the formation of 3. The molecular structure of the complex 4 was determined by X-ray crystallography and spectroscopic analysis.

Treatment of Pd(2)Cl(2)(CNC(6)H(3)Me(2)-2,6)(4) (1) with Mo(2)(O(2)CCF(3))(4) (2) in dichloromethane afforded an infinite zigzag chain [[Pd(2)Cl(2)(CNC(6)H(3)Me(2)-2,6)(4)][Mo(2)(O(2)CCF(3))(4)]](n) (3), where two metal-metal bonded dinuclear Pd-Pd and Mo-Mo units were bridged by chloro atoms. The Mo-Mo distance (2.1312(3) A) of 3 is significantly elongated compared to that of 2 (2.090(4) A) and lies in the range of that of the quadruple Mo-Mo bonded complexes. Such elongation might be attributed to the axial donation of the chloro atoms of the Pd-Pd unit to the Mo-Mo moiety.

The molecular structure of the title compound, [Al(CH3)2(C22H26NO)], displays a monomer with the AlIIIatom in a distorted tetrahedral environment defined by two methyl groups and the N and O atoms of the chelating ketiminate anion. The O—Al—N bite angle of the chelating ligand is 94.14 (9)°. The O—C—C—C—N backbone of the ligand is nearly coplanar (r.m.s. deviation = 0.029 Å) and the Al atom deviates significantly from the mean plane by 0.525 (3) Å. In the crystal, weak intermolecular C—H...O interactions are observed.

This paper reports the preparation of coral-shaped topological morphology nascent polyethylene (PE) particles promoted by the novel heterogeneous non-metallocene catalyst (m-CH3PhO)TiCl3/carbon nanotubes (CNTs), with AlEt3 used as a cocatalyst. Scanning electron microscope (SEM), high resolution transmission electron microscope (HR-TEM) and inductively coupled plasma (ICP) emission spectroscopy were used to determine the morphology of the catalyst particles and the content of (m-CH3PhO)TiCl3. The carbon nanotube surface was treated with Grignard Reagent prior to reacting with (m-CH3PhO)TiCl3. The catalyst system could effectively catalyze ethylene polymerization and ethylene with 1- hexene copolymerization, the catalytic activity could reach up to 5.8 kg/((gTi)h). Morphology of the obtained polymer particles by SEM and HR-TEM technique revealed that the nascent polyethylene particles looked like coral shape in micro-size. The multiwalled carbon nanotubes (MWCNTs) supported catalysts polymerized ethylene to form polymer nanocomposite in situ. The microscopic examination of this nanocomposite revealed that carbon nanoparticles in PE matrix had a good distribution and the cryogenically fractured surface was ductile-like when polymerization time was 2 min.

A new kind of inorganic–organic hybrid zirconium phosphonate material (NTAZP) with mesoporous structure was synthesized using nitrilotris(methylene)-triphosphonic acid (ATMP) and zirconium dichloride oxide octahydrate. The sample possesses a spherical morphology, and the spheres are composed of lobular lamellae. The lobular lamellae have the structure of a worm-like mesoporous (about 2.7 nm) framework and a high surface area (about 160.4 m2/g), which were characterized by SEM, TEM, N2 sorption, XRD, TG-DTA, elemental analysis, TOC (total organic carbon), XPS, and FT-IR spectroscopy techniques. The as-prepared NTAZP was used as adsorbent for the efficient removal of heavy metal ions (e.g., Pb2+, Cu2+, and Cd2+). Our results indicate that the material has good prospects for application as an adsorbent in wastewater processing.