含氟复鞣剂研究进展

含氟复鞣剂可以赋予皮革良好的手感、优异的透气性、抗水抗油性、抗污性等性能。阐述了合成含氟复鞣剂用含氟单体和非氟共聚单体的选择及其合成工艺 ,介绍了含氟复鞣剂的研究进展 ,指出含氟复鞣剂今后将会向着高质量、多功能化方向发展     

HIGH WATER ABSORBENTS FROM LIGNOCELLULOSES. I. EFFECT OF REACTION VARIABLES ON THE WATER ABSORBENCY OF POLYMERIZED LIGNOCELLULOSES

Hydrogels of 350 water-absorbency (g H₂O₂/g sample) and 900 water-keeping capacity (mL H₂O₂/g sample) were prepared from local lignocellulosic wastes. The wastes used are rice straw, sugar-cane bagasse, and cotton stalks. These hydrogels were prepared via graft–polymerization reaction using some vinyl monomers, followed by alkali hydrolysis. The effects of grafting parameters (concentration of both initiator and monomer, temperature, and time), purity of lignocellulose sample, type of monomer, pretreatment of lignocellulose, and manner of saponification reaction were examined.

The application of such polymeric materials as soil conditioners, by following the pore size distribution of sand soil, in comparison with conventional soil conditioners (e.g., natural organic fertilizer and clay), were also evaluated.     

Synthesis of a novel series of propargyloxyphenyl maleimides and their characterization as thermal‐resistance resins

Novel thermosetting monomers possessing both maleimide and propargyl groups were first designed and synthesized. The monomers included N‐(2‐propargyloxyphenyl) maleimide (2‐PPM), N‐(3‐propargyloxyphenyl) maleimide (3‐PPM), and N‐(4‐propargyloxyphenyl) maleimide (4‐PPM), and their structures were confirmed with Fourier transform infrared (FTIR) spectroscopy, ¹H‐NMR, and elemental analysis. The cure behaviors of these monomers were characterized with differential scanning calorimetry and FTIR spectroscopy, and the results indicated that the monomers had a broader processing window than normal bismaleimide (BMI) resins. The thermal properties of the cured monomers were characterized with thermogravimetric analysis and dynamic mechanical analysis. The 5% mass loss temperatures of the cured monomers were high (ca. 400°C), and the glass‐transition temperatures of cured 2‐PPM, 3‐PPM, and 4‐PPM were 386, 373, and 387°C, respectively, which were much higher than those of typical commercial blended BMI resins. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Synthesis and Characterization of Low Viscosity Dimethacrylic Resin Based on Isosorbide

In this article, synthesis and properties of novel dimethacrylic resin (ISETDMA) based on human friendly, biobased isosorbide was described. Its potential as a possible diluting monomer for medical applications, mainly dental restorative systems was assessed. The resin was obtained in two‐step synthesis including ethoxylation of isosorbide and subsequent methacrylation with methacryloyl chloride. ¹HNMR, FTIR, and electrospray ionization mass spectroscopy (ESI‐MS) techniques were used to identify products. ISETDMA as well as composition with 2,2‐bis[4‐(2‐hydroxy‐3‐methacryloyloxypropoxy)phenyl]propane were polymerized using UV initiator IRGACURE 651. Double bond conversion, polymerization shrinkage, water sorption, and sol fraction of resulting polymers were determined. Selected mechanical (flexural strength and modulus, Brinell hardness) and thermomechanical (dynamic mechanical analysis) properties were also investigated. Triethylene glycol dimethacrylate and 2,2‐bis(4‐(2‐methacryloxyethyl‐1‐oxy)phenyl)propane based homopolymers and copolymers were prepared as reference for comparison of particular properties. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2514–2522, 2013     

Synthesis and photopolymerization of phosphonic acid monomers for applications in compomer materials

Novel methacrylate monomers bearing phosphonic acid groups 1 and 2 as well as new sulfur methacrylates 9 and 10 have been prepared in good yields from thiophenol. They have been fully characterized by ¹H‐NMR, ¹³C‐NMR, ³¹P‐NMR, and HRMS. Their copolymerization with a bis‐GMA : TEGDMA (1 : 1) blend has been investigated with photodifferential scanning calorimetry at 50°C with camphorquinone as a photoinitiator and ethyl 4‐(dimethylamino)benzoate (EDAB) as a coinitiator. The higher the content of acidic monomer 1 or 2 incorporated in the bis‐GMA : TEGDMA (1 : 1) blend, the lower the mixtures reactivity. The phosphonic acid group has been proved to be responsible for this drop of reactivity. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

交联单体在丙烯酸弹性乳液中的应用

用不同的交联单体做交联剂，采用合适的工艺条件，合成了两种丙烯酸弹性乳液。讨论了两种弹性乳液所成膜的性能差别，及不同乳化剂对乳液性能的影响。     

Synthesis and polymerization of anthracene‐based itaconimides

Two new anthracene‐based itaconimides, ie N‐(1‐ and 2‐anthryl) itaconimides, were synthesized by the reaction of aromatic amines with itaconic anhydride, followed by itaconamic acid imidization. The same reaction failed in the case of anthracene‐ring substitution at the position 9′. Radical and thermal polymerization of N‐(1‐ and 2‐anthryl) itaconimides led to polymers with anthracene pendant groups. No self‐polymerization by Diels–Alder cycloaddition of the itaconic function (dienophile) and anthracene nucleus (diene) was observed, as is the case for N‐(anthryl) maleimides and citraconimides. Copyright © 2004 Society of Chemical Industry     

High performance UV-cured coatings for wood protection

UV-curable systems based on the copolymerisation of a typical acrylic resin with a low amount of a fluorinated monomer (<1%, w/w) were used for the protection of wood panels. In the presence of the additives, the bulk properties and the adhesion of the acrylic films were unchanged, while a strong modification of the surface was obtained. The quality aspects and the chemical resistance of the coatings applied to the wood panels were also enhanced.     

Mechanism of acetic acid transfer from aqueous sodium chloride solutions to some orgranic solvents

Salting out of acetic acid from aqueous solutions containing various concentrations of sodium chloride into some organic solvents has been studied at various temperatures. The solvents include cyclohexane, carbon tetrachloride, 1,2-dichloroethane, isopropyl ether, 2-pentanone and 1-heptanol. The results are consistent with a transfer mechanism involving monomer partitioning, dimerization and dimer return to the aqueous phase. Factors favoring monomer partitioning such as rise in both temperature and salt level retard dimer return, a process which is found to be significant in dimerization-enhancing solvents. The sensitivity of various solvents towards salt effect increases in the order 1-heptanol < isopropylether < 1,2-dichloroethane < 2-pentanone < cyclohexane < carbon tetrachloride which generally parallels in the reverse order the extent of stabilization of the acid by various solvent interactions.     

Synthesis and properties of side‐chain liquid‐crystalline polysiloxanes containing hemiphasmidic mesogens

The synthesis of hemiphasmidic monomers 4‐[(3,4,5‐triethoxy)benzoyloxy]‐4′‐[(p‐allyloxy)benzoyloxy]biphenyl (M₁), 4‐[(3,5‐diethoxy)benzoyloxy]‐4′‐[(p‐allyloxy)‐benzoyloxy]biphenyl (M₂), and of the corresponding side‐chain liquid‐crystalline polysiloxanes (P₁, P₂) was carried out. For comparison, rodlike monomer 4‐[(p‐ethoxy)‐benzoyloxy]‐4′‐[(p‐allyloxy)benzoyloxy]biphenyl (M₃) and its polysiloxanes (P₃) were also prepared. The chemical structures of the monomers and polymers obtained were confirmed by FTIR and ¹H‐NMR spectra. Their mesomorphic properties and phase behavior were investigated by differential scanning calorimetry, polarizing optical microscopy, and X‐ray diffraction measurements. The relationship between structures and properties was discussed. It was observed that M₁ and M₃ were enantiotropic nematic phase, M₂ was monotropic mesophase, and their poly(methylsiloxanes) (P₁–P₃) possessed a broad range enantiotropic nematic phases and high thermal stability. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 946–952, 2005