scholarly journals Metallocene Catalyzed Homopolymerization of Propylene with a <i>C</i><sub>2</sub> Symmetric Isospecific Zirconecene/MMAO Catalysts under Different Polymerization Conditions

2020 ◽  
Vol 10 (03) ◽  
pp. 27-34
Author(s):  
Benard Oloo Nyangoye ◽  
Benard Odhiambo Obondo
Keyword(s):  
Polymerization Conditions

Fabrication of Conductive Textile via Chemical Oxidative Polymerization of Aniline on Polyester Cloth

2018 ◽  
Author(s):  
alireza razaghi
Keyword(s):  
Acidic Solution ◽  
Oxidative Polymerization ◽  
Morphological Structure ◽  
Infrared Spectrometry ◽  
Aniline Monomer ◽  
Polyester Textile ◽  
Conductive Polyaniline ◽  
Conductive Textile ◽  
Polymerization Conditions ◽  
Aniline Polymerization

In this research aniline polymerization conditions were optimized in presence of pre-treated polyester textile to achieve as high electrical conductivity as 100 S/Cm. Alkaline activation of the polyester textile was followed by immersion in to aqueous acidic solution of aniline monomer. Then the oxidant solution was used to initiate the polymerization. Finally, the prepared product was washed and dried prior to ant test. Functional groups were studied by Fourie-transformed infrared spectrometry (FTIR) from the surface of the polyaniline coated textile. Also, morphological structure of synthesized conductive polyaniline was studied by scanning electron microscopy (SEM). The synthesized cloth was used in a closed circuit in order to light up alight emitting diode to emphasis the conductivity of the textile and fibres that synthesised by this method.

Fabrication of Conductive Textile via Chemical Oxidative Polymerization of Aniline on Polyester Cloth

2018 ◽  
Author(s):  
alireza razaghi
Keyword(s):  
Acidic Solution ◽  
Oxidative Polymerization ◽  
Morphological Structure ◽  
Infrared Spectrometry ◽  
Aniline Monomer ◽  
Polyester Textile ◽  
Conductive Polyaniline ◽  
Conductive Textile ◽  
Polymerization Conditions ◽  
Aniline Polymerization

In this research aniline polymerization conditions were optimized in presence of pre-treated polyester textile to achieve as high electrical conductivity as 100 S/Cm. Alkaline activation of the polyester textile was followed by immersion in to aqueous acidic solution of aniline monomer. Then the oxidant solution was used to initiate the polymerization. Finally, the prepared product was washed and dried prior to ant test. Functional groups were studied by Fourie-transformed infrared spectrometry (FTIR) from the surface of the polyaniline coated textile. Also, morphological structure of synthesized conductive polyaniline was studied by scanning electron microscopy (SEM). The synthesized cloth was used in a closed circuit in order to light up alight emitting diode to emphasis the conductivity of the textile and fibres that synthesised by this method.

scholarly journals Poly(lactic Acid): A Versatile Biobased Polymer for the Future with Multifunctional Properties—From Monomer Synthesis, Polymerization Techniques and Molecular Weight Increase to PLA Applications

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1822
Author(s):  
Evangelia Balla ◽  
Vasileios Daniilidis ◽  
Georgia Karlioti ◽  
Theocharis Kalamas ◽  
Myrika Stefanidou ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Lactic Acid ◽  
Chain Extension ◽  
Poly Lactic Acid ◽  
Plastic Pollution ◽  
Practical Applications ◽  
Decomposition Reactions ◽  
Melt Polycondensation ◽  
Polymerization Conditions ◽  
Molecular Weight Increase

Environmental problems, such as global warming and plastic pollution have forced researchers to investigate alternatives for conventional plastics. Poly(lactic acid) (PLA), one of the well-known eco-friendly biodegradables and biobased polyesters, has been studied extensively and is considered to be a promising substitute to petroleum-based polymers. This review gives an inclusive overview of the current research of lactic acid and lactide dimer techniques along with the production of PLA from its monomers. Melt polycondensation as well as ring opening polymerization techniques are discussed, and the effect of various catalysts and polymerization conditions is thoroughly presented. Reaction mechanisms are also reviewed. However, due to the competitive decomposition reactions, in the most cases low or medium molecular weight (MW) of PLA, not exceeding 20,000–50,000 g/mol, are prepared. For this reason, additional procedures such as solid state polycondensation (SSP) and chain extension (CE) reaching MW ranging from 80,000 up to 250,000 g/mol are extensively investigated here. Lastly, numerous practical applications of PLA in various fields of industry, technical challenges and limitations of PLA use as well as its future perspectives are also reported in this review.

Sulfone-functionalized poly(p-phenylene terephthalamide) copolymer fibers with improved interfacial adhesion to epoxy matrices

2021 ◽  
pp. 095400832110089
Author(s):  
Ting Li ◽  
Zengxiao Wang ◽  
Hao Zhang ◽  
Yutong Cao ◽  
Zuming Hu ◽  
...  
Keyword(s):  
Interfacial Adhesion ◽  
Interfacial Shear Strength ◽  
Aramid Fiber ◽  
Fiber Reinforced Composites ◽  
Epoxy Composites ◽  
Reinforced Composites ◽  
Fiber Reinforced ◽  
Regular Arrangement ◽  
Epoxy Matrices ◽  
Polymerization Conditions

The poor interfacial adhesion of aramid fiber and matrix limits the application of the final composites. In this study, a series of the sulfone-functionalized poly( p-phenylene terephthalamide) (SPPTA) copolymers were satisfactorily synthesized and the effects of polymerization conditions (contents of the additional monomer and the cosolvent LiCl, molar concentration and ratio of the monomer, reaction temperature and time) on the molecular weight of the copolymer were discussed. The introduction of the sulfone group in aromatic polyamides not only increased the polarity of poly( p-phenylene terephthalamide) (PPTA) but destroyed the regular arrangement of the molecular chains, which greatly improved the surface free energy and the solubility of the polymers in organic solvents. The polymer maintained excellent thermal and interfacial properties. Compared with the PPTA fiber/epoxy composites, the interfacial shear strength (IFSS) of SPPTA fiber-reinforced epoxy composites reached 43.5 MPa, with a significantly enhancement of 20.8%, implying that the study provided an effective method to achieve highly interfacial adhesion of aramid fiber-reinforced composites.

Emulsion polymerization of ethylene. IV. Effect of recipe and polymerization conditions on polymer properties

1966 ◽  
Vol 10 (12) ◽  
pp. 1845-1862 ◽  
Author(s):  
Gerald J. Mantell ◽  
Harry K. Stryker ◽  
Arthur F. Helin ◽  
Donald R. Jamieson ◽  
Charles H. Wright
Keyword(s):  
Emulsion Polymerization ◽  
Polymer Properties ◽  
Polymerization Conditions

scholarly journals The influence of polymerization conditions on color stability of three indirect composite materials

2013 ◽  
Vol 55 (1) ◽  
pp. 51-55 ◽  
Author(s):  
Hideyuki Imai ◽  
Hiroyasu Koizumi ◽  
Keiichi Sasaki ◽  
Hideo Matsumura
Keyword(s):  
Composite Materials ◽  
Color Stability ◽  
Indirect Composite ◽  
Polymerization Conditions

scholarly journals The Roll of NaPSS Surfactant on the Ceria Nanoparticles Embedding in Polypyrrole Films

2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Simona Popescu ◽  
Mihaela Mîndroiu ◽  
Daniela Cabuzu ◽  
Cristian Pîrvu
Keyword(s):  
Cerium Oxide ◽  
Antibacterial Effect ◽  
Electrochemical Behaviour ◽  
Titanium Substrate ◽  
Crystalline Form ◽  
Polymeric Films ◽  
Ceria Nanoparticles ◽  
Polypyrrole Films ◽  
Polymerization Conditions

Cerium oxide nanoparticles (CeO2NPs) in crystalline form have been synthesized by a coprecipitation method. CeO2nanoparticles were then embedded in polypyrrole (PPy) films during the electropolymerization of pyrrole (Py) on titanium substrate. The influence of poly(sodium 4-styrenesulfonate) (NaPSS) surfactant used during polymerization on the embedding of CeO2NPs in polypyrrole films was investigated. The new films were characterized in terms of surface analysis, wettability, electrochemical behaviour, and antibacterial effect. The surface and electrochemical characterization revealed the role of surfactant on PPy doping process cerium oxide incorporation. In the presence of surfactant, CeO2NPs are preferentially embedded in the polymeric film while, without surfactant, the ceria nanoparticles are quasiuniformly spread as agglomerates onto polymeric films. The antibacterial effect of studied PPy films was substantially improved in the presence of cerium oxide and depends by the polymerization conditions.

Sign in / Sign up

Export Citation Format

Share Document