scholarly journals Porous poly(methylmethacrylate) and poly(methylmethacrylate-co-acrylamide)

2006 ◽  
Vol 60 (11-12) ◽  
pp. 327-332 ◽  
Author(s):  
Ljubisa Nikolic ◽  
Vesna Nikolic ◽  
Miroslav Stankovic ◽  
Zoran Todorovic ◽  
Zorica Vukovic
Keyword(s):  
Methyl Methacrylate ◽  
Mercury Porosimetry ◽  
Sol Gel ◽  
Vinyl Pyrrolidone ◽  
Cross Linking ◽  
Poly Methyl Methacrylate ◽  
Whole Cells ◽  
Sulfosuccinate Sodium ◽  
The Cross ◽  
Poly Vinyl Pyrrolidone

The characteristics of two types of porous polymers: poly(methyl methacrylate) and copolymers of methyl methacrylate and acrylamide were investigated in this study. Poly(methyl methacrylate) was synthesized in suspension, using ethylene glycol dimethacrylate as the cross-linking agent, poly(vinyl pyrrolidone) as the protective colloid, and benzoyl peroxide as the initiator. The synthesis of poly(methyl methacrylate-co-acrylamide) was initiated in emulsion in the presence of dioctyl sulfosuccinate sodium salt, followed by a sol-gel process, and completely reacted to the solid state. Potassium persulfate was used as the initiator, and tetramethylol glycoluril as the cross-linking agent. Both types of syntheses were carried out in the presence of ethyl acetate. The porosity, specific surface and distribution of the pore sizes of the obtained polymers were determined by mercury porosimetry. The polymers were used as inert carriers for the immobilization of enzymes and whole cells of Saccharomyces cerevisiae yeast.

Preparation and Properties of poly (n-butyl acrylate)/ poly (methyl methacrylate-co-styrene) Emulsion Polymer with Pentaerythritol Triacrylate as a Cross-Linking Agent

2013 ◽  
Vol 774-776 ◽  
pp. 927-930
Author(s):  
Li Yong Jiao ◽  
Gang Yuan ◽  
Yun Peng Qi ◽  
Lin Lin Li
Keyword(s):  
Mechanical Properties ◽  
Methyl Methacrylate ◽  
Butyl Acrylate ◽  
Water Resistance ◽  
Cross Linking ◽  
Seeded Emulsion Polymerization ◽  
Poly Methyl Methacrylate ◽  
Emulsion Polymer ◽  
Pentaerythritol Triacrylate ◽  
The Cross

A series of cross-linking core-shell structured poly (n-butyl acrylate) /poly (methyl methacrylate-co-styrene) emulsion polymer were prepared by semi-batch seeded emulsion polymerization with pentaerythritol triacrylate (PETA) as a cross-linking agent. The emulsion polymers were characterized by Fourier transform infrared spectra (FTIR) and transmission electron microscope (TEM), respectively. The influences of cross-linking agent content on the water resistance and mechanical properties of the emulsion films were investigated. The films prepared by the emulsion polymer with the cross-linking agent exhibited excellent water resistance, and mechanical properties (tensile strength and flexility), resulting from the cross-linking structure of shell segments compared with that prepared without cross-linking agent. The film of the emulsion polymer with 1.0wt% cross-linking agent exhibited better comprehensive performance.

scholarly journals Fabrication of Substituted-Hydroxyapatite/Poly(vinyl pyrrolidone)- Poly(methyl methacrylate) Biocomposites for Bone Tissue Engineering Applications

2021 ◽  
Vol 33 (11) ◽  
pp. 2774-2780
Author(s):  
G. Priya ◽  
N. Vijayakumari
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Methyl Methacrylate ◽  
Antimicrobial Activities ◽  
Vinyl Pyrrolidone ◽  
Gram Negative Bacteria ◽  
Structural Investigations ◽  
Gram Negative ◽  
Poly Methyl Methacrylate ◽  
Poly Vinyl Pyrrolidone

Present work based on the development and incorporation of zinc-cerium substituted hydroxyapatite (ZCHA) nanoparticles into the host material of the dual polymer blend of poly(vinyl pyrrolidone) (PVD)-poly(methyl methacrylate) (PMMA). Numerous characterization techniques such as FTIR, XRD and SEM-EDX have been used in morphological and structural investigations of prepared nanoparticles and ZCHA reinforced PMMA-PVD biocomposites. The mechanical properties of ZCHA/PVD-PMMA biocomposites, like compressive strength was evaluated. To examine the biocompatibility of biocomposites, hemocompatibility experiments have been carried out. The antimicrobial activities of biocomposites toward Gram-positive and Gram-negative bacteria have also been tested and the cytotoxic existence of biocomposites has been evaluated using the MTT assay experiment. The developed ZCHA/PVD-PMMA biocomposites is suggested to provide the finest medicinal benefits in the application of biomaterials.

EXPERIMENTAL VALIDATION OF THE CHARLESBY AND HORIKX MODELS APPLIED TO DE-VULCANIZATION OF SULFUR AND PEROXIDE VULCANIZATES OF NR AND EPDM

2016 ◽  
Vol 89 (4) ◽  
pp. 671-688 ◽  
Author(s):  
M. A. L. Verbruggen ◽  
L. van der Does ◽  
W. K. Dierkes ◽  
J. W. M. Noordermeer
Keyword(s):  
Experimental Validation ◽  
Main Chain ◽  
Sol Gel ◽  
Chain Scission ◽  
Cross Linking ◽  
Cross Link ◽  
Practical Reality ◽  
Cross Links ◽  
The Cross ◽  
Theoretical Considerations

ABSTRACT The theoretical model developed by Charlesby to quantify the balance between cross-links creation of polymers and chain scission during radiation cross-linking and further modifications by Horikx to describe network breakdown from aging were merged to characterize the balance of both types of scission on the development of the sol content during de-vulcanization of rubber networks. There are, however, disturbing factors in these theoretical considerations vis-à-vis practical reality. Sulfur- and peroxide-cured NR and EPDM vulcanizates were de-vulcanized under conditions of selective cross-link and random main-chain scissions. Cross-link scission was obtained using thiol-amine reagents for selective cleavage of sulfur cross-links. Random main-chain scission was achieved by heating peroxide vulcanizates of NR with diphenyldisulfide, a method commonly employed for NR reclaiming. An important factor in the analyses of these experiments is the cross-linking index. Its value must be calculated using the sol fraction of the cross-linked network before de-vulcanization to obtain reliable results. The values for the cross-linking index calculated with sol-gel data before de-vulcanization appear to fit the experimentally determined modes of network scission during de-vulcanization very well. This study confirms that the treatment of de-vulcanization data with the merged Charlesby and Horikx models can be used satisfactorily to characterize the de-vulcanization of NR and EPDM vulcanizates.

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