Influence of minute metal ions on the idle time of acrylamide polymerization in gelcasting of ceramics

Zhao, Lei; Yang, Jinlong; Ma, Liguo; Huang, Yong

doi:10.1016/s0167-577x(02)00660-2

Cited by 12 publications

(2 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore, the free radical generation is accelerated and the gel time becomes shorter. The mechanism of one of these reactions was expressed by the following equations :

Fe {(H_{2} O)}_{6}^{2 +} \to Fe {(H_{2} O)}_{5} O H^{+} + H^{+}

K_{d} = K_{1} + K_{2} (H^{+})

where K d is the rate coefficient of initiation of (NH 4 ) 2 S 2 O 8 , and K 1 and K 2 are the rate coefficient of initiation reaction without acid and the rate coefficient of initiation reaction with acid, respectively.…”

Section: Resultsmentioning

confidence: 99%

Chemorheological behavior of β-SiAlON aqueous suspensions in gelcasting process

2013

View full text Add to dashboard Cite

The chemorheological behavior of an aqueous suspension of monofunctional and difunctional monomers containing b-SiAlON was investigated for gelcasting process. The effect of various parameters on gel and processing times was also studied. The time-temperature-transformation (TTT) diagram was used to correlate the pertinent processing parameters (time and temperature) with the gelation and processing times during in situ polymerization. The significant difference noticed between TTT diagrams of gel system containing b-SiAlON and a pure gel system was a sharp shift of castable region to lower temperatures. This shift indicates that at the same monomers and initiator concentrations, the gelation can occur at lower temperature in the presence of SiAlON. These results clearly imply that the ingredient has accelerating effect on the polymerization reaction of acrylamide/methylene bisacrylamide. Reduction of polymerization activation energy from 72 kJ/mol for the monomer solution to 61 kJ/mol for a suspension containing SiAlON (35 vol%) confirmed this result. The impurities and surface groups of SiAlON are responsible for the accelerating effect of SiAlON. Furthermore, all suspensions showed shear thinning behavior, which were enhanced by b-SiAlON rate of concentration increase. POLYM. ENG.

show abstract

“…Therefore, the free radical generation is accelerated and the gel time becomes shorter. The mechanism of one of these reactions was expressed by the following equations :

Fe {(H_{2} O)}_{6}^{2 +} \to Fe {(H_{2} O)}_{5} O H^{+} + H^{+}

K_{d} = K_{1} + K_{2} (H^{+})

Section: Resultsmentioning

confidence: 99%

Chemorheological behavior of β-SiAlON aqueous suspensions in gelcasting process

2013

View full text Add to dashboard Cite

show abstract

“…Conductive filler generally scatters through organic vehicle in form of piece, sphericity and threadiness establishing conductive network which determines conductivity of electrocondution slurry [2] . Nowadays various silver powders are regarded as subjective conductive phase among about 80% thousands of electronic pate products adopts [3] , but silver paste is problematic. It tends to be expensive, diffusion under the influence of direct current, and vulcanization easily.…”

Section: Introductionmentioning

confidence: 99%

Preparation and Performance of Silver Coated Copper Powder

Sun

Wang

Xiao

et al. 2013

AMR

View full text Add to dashboard Cite

Different parameters are used to characterize the conductivity of copper powder with silver plating. Ethanediamine（C2H8N2） is employed to adjust the pH value of plating solution (solution A), and chelate Cu2+ generated by side reaction, forming sound five-membered ring structure with Cu2+, thus preventing the formation of Cu(NH3)42+ which can avoid adsorption of Cu(NH3)42+ on the surface of copper powder. In this way silver-plated copper powder with conductivity equal to fine silver powder can be obtained, the effects of dosage of C2H8N2 and Tollens' reagent concentration on performance of silver-plated copper powder have also been investigated. The result shows that dosage of C2H8N2 has significant effects on electrical conductivity of silver-plated copper powder. The dosage of C2H8N2 should ensure that pH value of control solution A maintains 9.0~10.0. The concentration of Tollens' reagent should make sure that the generated silver-plated copper powder is most even and continuous and tightness when silver particles in form of heterogeneous nucleation is surrounded on the surface of copper powder, , and the optimum concentration is 0.09mol/L. The conductivity of silver-plated copper powder made by Tollens' reagent with 0.09mol/L concentration is optimal, which is 3.9×10-4Ω•cm,when adjusting the pH value of solution A to 9.5 by C2H8N2 control.

show abstract

Generation, Development, Inheritance, and Control of the Defects during the Transformation from Suspension to Green Body

Huang

Yang

2010

Novel Colloidal Forming of Ceramics

View full text Add to dashboard Cite

Influence of minute metal ions on the idle time of acrylamide polymerization in gelcasting of ceramics

Cited by 12 publications

References 7 publications

Chemorheological behavior of β-SiAlON aqueous suspensions in gelcasting process

Chemorheological behavior of β-SiAlON aqueous suspensions in gelcasting process

Preparation and Performance of Silver Coated Copper Powder

Generation, Development, Inheritance, and Control of the Defects during the Transformation from Suspension to Green Body

Contact Info

Product

Resources

About