Syntheses and Structures of Gallyliron Complexes with Pyridine Ligands and Their Reactions with Methyl Acrylate

2021 ◽  
Author(s):  
Takako Muraoka ◽  
Yasuhisa Ishii ◽  
Nursaliha Siti ◽  
Masahiro Nasu ◽  
Nurul Ain Wahida ◽  
...  
Keyword(s):  
Methyl Acrylate ◽  
Pyridine Ligands

Biomedical Materials to Repair Retinal Detachments

1985 ◽  
Vol 55 ◽  
Author(s):  
Miguel F. Refojo
Keyword(s):  
Retinal Detachment ◽  
Silicone Rubber ◽  
Methyl Acrylate ◽  
Silicone Oil ◽  
Vitreous Body ◽  
Light Sensitivity ◽  
Scleral Buckling ◽  
Intraocular Injection ◽  
Other Substances

ABSTRACTImplants are essential for the repair of retinal detachments. The implant buckles the wall of the eye and apposes the detached retina with the choroid, thus restoring light sensitivity to the retina. The scleral buckling also relieves traction on the retina from a shrinking vitreous body. The implant materials most commonly used are solid silicone rubber and silicone sponges, but both types have some disadvantages. A poly(hydroxyethyl acrylate-co-methyl acrylate) hydrogel implant with improved properties of softness and antibiotic absorption is also available for retinal detachment surgery. Proliferative vitreoretinopathy involves various conditions of retinal detachment complicated by vitreous fibrosis, which, after vitrectomy, may be treated with intraocular injection of fluids that support the retina against the choroid. For conditions requiring a long-term implant, silicone oil although controversial is the material of choice. Many other substances have been investigated but none better has yet been found.

Comparison of the viscoelastic penetration and tensile behaviour of poly(methyl acrylate) and poly(ethyl acrylate)

1979 ◽  
Vol 44 (6) ◽  
pp. 1942-1948 ◽  
Author(s):  
Jaroslav Hrouz ◽  
Michal Ilavský ◽  
Ivan Havlíček ◽  
Karel Dušek
Keyword(s):  
Methyl Acrylate ◽  
Poisson Ratio ◽  
Young Modulus ◽  
Ethyl Acrylate ◽  
Sample Volume ◽  
Viscoelastic Behaviour ◽  
Tensile Behaviour ◽  
Temperature Superposition ◽  
Main Transition

The viscoelastic penetration and tensile behaviour of poly(methyl acrylate) and poly(ethyl acrylate) in the main transition region have been investigated. It was found that the time-temperature superposition could be carried out in the case of the penetration viscoelastic behaviour; the temperature dependence of the penetration and tensile shift factors was the same. The superimposed curves of the penetration and Young modulus allowed us to calculate the dependence of the Poisson ratio and thus to characterize the change in sample volume with deformation. It was demonstrated that the penetration method of determination of the viscoelastic behaviour is equivalent to the tensile method.

scholarly journals Bis(dicyanamido-κN)tetrakis(pyridine-κN)nickel(II)

2012 ◽  
Vol 68 (6) ◽  
pp. m745-m745
Author(s):  
Susanne Wöhlert ◽  
Mario Wriedt ◽  
Inke Jess ◽  
Christian Näther
Keyword(s):  
Crystal Structure ◽  
Title Compound ◽  
Space Group ◽  
Pyridine Ligands ◽  
Anionic Ligands

In the crystal structure of the title compound, [Ni(C2N3)2(C5H5N)4], the NiII cations are coordinated by four pyridine ligands and two dicyanamide anions into discrete complexes. The shortest Ni...Ni separation is 8.1068 (10) Å. The structure is pseudo-centrosymmetric and can also be refined in the space group C2/c in which both anionic ligands are strongly disordered and the refinement leads to significantly poorer reliability factors.

scholarly journals Fabrication and Characterization of Electrospun Poly(acrylonitrile-co-Methyl Acrylate)/Lignin Nanofibers: Effects of Lignin Type and Total Polymer Concentration

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 992
Author(s):  
Suchitha Devadas ◽  
Saja M. Nabat Al-Ajrash ◽  
Donald A. Klosterman ◽  
Kenya M. Crosson ◽  
Garry S. Crosson ◽  
...  
Keyword(s):  
Methyl Acrylate ◽  
Lignin Content ◽  
Polymer Concentration ◽  
Weight Ratio ◽  
Electrospun Nanofibers ◽  
Polymer Content ◽  
Blend Ratio ◽  
Blend Ratios ◽  
Poly Acrylonitrile

Lignin macromolecules are potential precursor materials for producing electrospun nanofibers for composite applications. However, little is known about the effect of lignin type and blend ratios with synthetic polymers. This study analyzed blends of poly(acrylonitrile-co-methyl acrylate) (PAN-MA) with two types of commercially available lignin, low sulfonate (LSL) and alkali, kraft lignin (AL), in DMF solvent. The electrospinning and polymer blend solution conditions were optimized to produce thermally stable, smooth lignin-based nanofibers with total polymer content of up to 20 wt % in solution and a 50/50 blend weight ratio. Microscopy studies revealed that AL blends possess good solubility, miscibility, and dispersibility compared to LSL blends. Despite the lignin content or type, rheological studies demonstrated that PAN-MA concentration in solution dictated the blend’s viscosity. Smooth electrospun nanofibers were fabricated using AL depending upon the total polymer content and blend ratio. AL’s addition to PAN-MA did not affect the glass transition or degradation temperatures of the nanofibers compared to neat PAN-MA. We confirmed the presence of each lignin type within PAN-MA nanofibers through infrared spectroscopy. PAN-MA/AL nanofibers possessed similar morphological and thermal properties as PAN-MA; thus, these lignin-based nanofibers can replace PAN in future applications, including production of carbon fibers and supercapacitors.

scholarly journals One-pot synthesis for gradient copolymers via concurrent tandem living radical polymerization: mild and selective transesterification of methyl acrylate through Al(acac)3 with common alcohols

RSC Advances ◽  
2021 ◽  
Vol 11 (42) ◽  
pp. 26049-26055
Author(s):  
Tam Thi-Thanh Huynh ◽  
Si Eun Kim ◽  
Soon Cheon Kim ◽  
Jin Chul Kim ◽  
Young Il Park ◽  
...  
Keyword(s):  
Radical Polymerization ◽  
Methyl Acrylate ◽  
Living Radical Polymerization ◽  
One Pot ◽  
Gradient Copolymers ◽  
One Pot Synthesis

The acrylate based gradient copolymers were successfully synthesized by concurrent tandem living radical polymerization using Al(acac)3 as cocatalyst with common alcohols.

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