Structure and Properties of Filled Stocks XVI. Polybutadiene Filled with Colloidal Silica

1959 ◽  
Vol 32 (2) ◽  
pp. 639-646
Author(s):  
B. Dogadkin ◽  
K. Pechkovskaya ◽  
E. Gol'dman
Keyword(s):  
Colloidal Silica ◽  
Chain Structure ◽  
Binary Solvents ◽  
Structure And Properties ◽  
Simple Method ◽  
Reinforcing Effect ◽  
Filled Rubber ◽  
Equilibrium Swelling ◽  
Rubber Stock ◽  
Filler Activity

Abstract 1. Colloidal silica can be partially or completely removed from filled rubber stocks by boiling in 1% aqueous NaOH. 2. Degree and rate of extracting directly depend on the reinforcing effect of the silica. The higher the filler activity, the more complete its extractability from the rubber. Inactive samples of silica practically cannot be extracted from filled rubber stocks. 3. The active silica forms a thixotropic chain structure in the rubber, but inactive silica is distributed in rubber as isolated particles or aggregates. 4. The rubber portion that remains after extraction of the active silica is insoluble in common rubber solvents. 5. The equilibrium swelling value in binary solvents (butanol-toluene) is lower, the higher the reinforcing action of the silica. 6. The reinforcing effect of silica is proportional to its moisture takeup capacity, which may be determined by a simple method described. 7. Based on the experiments described, the type of linkages involved and the structure of the rubber stock filled with silica are considered.

Modeling Gel Swelling in Binary Solvents: A Thermodynamic Approach to Explaining Cosolvency and Cononsolvency Effects

2019 ◽  
Vol 11 (05) ◽  
pp. 1950050 ◽  
Author(s):  
Rui Xiao ◽  
Jin Qian ◽  
Shaoxing Qu
Keyword(s):  
Lattice Model ◽  
Thermodynamic Theory ◽  
Binary Solvents ◽  
Thermodynamic Approach ◽  
Solvent Mixtures ◽  
Solvent Interactions ◽  
Equilibrium Swelling ◽  
Acceptable Agreement ◽  
Swelling Behaviors ◽  
Solvent Solvent

If gel swells in binary solvents, two unusual phenomena may appear. Two solvents with relatively low swelling ability may become a good solvent for the polymer with high swelling ability when mixed, which is known as a cosolvency effect. In contrast, a cononsolvency effect indicates polymer is less soluable in solvent mixtures than it is in each of the cosolvents. In this work, we develop a thermodynamic theory to describe the equilibrium swelling behaviors of gels in binary solvents based on the Flory–Huggins lattice model. The model can reproduce both cosolvency and cononsolvency effects, showing that these effects are caused by the preferential absorption of the solvent by polymer together with solvent–solvent interactions. The model is also applied to describe experimentally observed cosolvency and cononsolvency effects in the literature, which shows an acceptable agreement.

scholarly journals Preparation, Structure and Properties of Acid Aqueous Solution Plasticized Thermoplastic Chitosan

Polymers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 818 ◽  
Author(s):  
Yu Zhang ◽  
Biao-Lan Liu ◽  
Liang-Jie Wang ◽  
Ying-Hua Deng ◽  
Shi-Yi Zhou ◽  
...  
Keyword(s):  
Hydrochloric Acid ◽  
Acid Solution ◽  
Solution Concentration ◽  
Structure And Properties ◽  
X Ray Diffraction ◽  
Simple Method ◽  
Characterization Methods ◽  
Modified Chitosan ◽  
Acid Aqueous Solution ◽  
And Performance

This work provides a simple method for the preparation of thermoplastic chitosan using the most common dilute inorganic and organic acids in aqueous solutions, namely hydrochloric acid (HCl) and acetic acid (HAc). The melting plasticization behavior of chitosan under different concentrations and types of acid solution was investigated. By means of infrared spectra (IR), scanning electron microscope (SEM), X-ray diffraction (XRD), and other characterization methods, as well as a mechanical property test, it was found that as the acid solution concentration increased, the protonation effect was stronger and the plasticization performance showed a better trend. The structure and performance of the modified chitosan were optimal when the concentration of HCl was around 8 wt %. In addition, it was found that HCl had a better effect on the plasticization of chitosan than HAc, which was because the protonation ability of HCl was stronger than that of HAc. Unlike the casting method, the structure and properties of chitosan sheets prepared by thermoplastic processing were directly affected by protonation, however not by the interaction of anionic-cationic electrostatic attractions between the –NH3+ groups of chitosan chains and the carboxyl groups of acetic acids or the chloridoid groups of hydrochloric acid.

Effect of Carbon Black on Crosslinking

2003 ◽  
Vol 76 (2) ◽  
pp. 517-532 ◽  
Author(s):  
A. N. Gent ◽  
J. A. Hartwell† ◽  
Ginger Lee
Keyword(s):  
Elastic Modulus ◽  
Carbon Black ◽  
Rubber Particle ◽  
Filled Rubber ◽  
Particle Bonding ◽  
Rubber Compounds ◽  
Equilibrium Swelling ◽  
Actual Degree ◽  
Equilibrium Swelling Ratios

Abstract For a number of different vulcanization systems, the equilibrium swelling ratios for carbon-black-filled and unfilled samples are shown to be linearly related, as found by Lorenz and Parks, indicating that the degree of crosslinking is not changed by incorporating carbon black. However, filled compounds swell less, and thus the apparent degree of crosslinking is significantly greater. For example, it is about twice as large for compounds containing 50 phr of HAF carbon black. This is confirmed by measurements of the elastic modulus of swollen samples. Relatively strong bonds appear to be formed between rubber molecules and the surface of carbon black particles - bonds that can withstand swelling stresses and temperatures of up to 120 °C. Bonding between rubber and carbon black is also indicated by the limited swelling of filled rubber compounds even before vulcanization, although in this case the apparent degree of crosslinking is smaller. Thus, vulcanization appears to enhance the contribution of rubber-particle bonding to the elastic modulus and restricted swelling of carbon-black-filled vulcanizates. Simple procedures are suggested for estimating the actual degree of crosslinking in filled rubber vulcanizates from measurements of equilibrium swelling or elastic modulus.

Investigation of Antibacterial Property and Photocatalytic Activity of Recyclable Ag/ZnOw Composites

2014 ◽  
Vol 472 ◽  
pp. 831-834
Author(s):  
Jie Wang ◽  
Xiao Yong Pan ◽  
Ling Peng ◽  
Yu Liu ◽  
Nian Jie Wang
Keyword(s):  
Silver Nanoparticles ◽  
Photocatalytic Performance ◽  
Antibacterial Property ◽  
Photocatalytic Property ◽  
Molar Ratio ◽  
Structure And Properties ◽  
Simple Method ◽  
Molar Ratios ◽  
Photocatalytic Activities ◽  
Oxide Whisker

Silver-deposited zinc oxide whisker (Ag/ZnOw) composites with different Ag/Zn molar ratios (MRs) were successfully synthesized by a simple method. Subsequently, the structure and properties of these composites were characterized using various tests. It is found that the silver nanoparticles are located on the root of ZnOw, which is beneficial for the antibacterial and photocatalytic performance of ZnOw. The Ag/ZnOw composite exhibits better antibacterial and photocatalytic activities than that of the pure ZnOw, and the efficiency of both properties increase with increasing molar ratio of Ag/Zn. Moreover, the mechanism which governs the photocatalytic property of the composite has also been discussed thoroughly.

Preparation and Properties of Rubberlike High Polymers. IV. Correlation between Structure and Properties of Elastomers Derived from Dienes

1948 ◽  
Vol 21 (2) ◽  
pp. 377-397
Author(s):  
G. Salomon ◽  
C. Koningsberger
Keyword(s):  
Natural Rubber ◽  
Elevated Temperatures ◽  
Elastic Recovery ◽  
Chain Structure ◽  
Complex Compounds ◽  
Structure And Properties ◽  
Straight Chain ◽  
Gutta Percha ◽  
Brittle Point ◽  
Derivatives Of

Abstract The correlation between structure and properties of elastomers prepared from dienes, natural rubber, gutta-percha, as well as those of some significant derivatives of natural rubber, are discussed. The similar influence exerted by methyl groups on the brittle point, elastic recovery, and permeability to gases is demonstrated and separated from the effect caused by insertion of —CH2— CHR— groups in straight-chain polybutadiene, which takes place during co-polymerization or 1,2 addition. The preponderant influence of an unbranched-chain structure on tensile strength at elevated temperatures and in the swollen state is illustrated. Complex compounds with silver nitrate provide further evidence for the particular symmetry of the natural rubber chain: They are reinforcing agents for synthetic elastomers. The brittle points of hydrochlorides from natural rubber, gutta-percha, and polyisoprene are compared with those of polyvinyl compounds. Correlation between the structure of molecular units in a polymeric paraffin derivative and its elasticity is pointed out.

Magnetic and Electronic Properties of Three New Hetero-Bimetallic Coordination Frameworks [Ru2(O2CR)4][Au(CN)2] (R = Benzoic Acid, Furan-2-carboxylate, or Thiophen-2-carboxylate)

2014 ◽  
Vol 67 (11) ◽  
pp. 1607 ◽  
Author(s):  
Michael J. Murphy ◽  
Tony D. Keene ◽  
Jason R. Price ◽  
Deanna M. D'Alessandro ◽  
Cameron J. Kepert
Keyword(s):  
Electronic Properties ◽  
Chain Structure ◽  
Magnetic Behaviour ◽  
Zero Field ◽  
Dimensional Chain ◽  
Structure And Properties ◽  
Zero Field Splitting ◽  
One Dimensional ◽  
The One ◽  
Coordination Frameworks

The crystal structures and magnetic and electronic properties of three new hetero-bimetallic coordination frameworks, [Ru2(O2CR)4][Au(CN)2] (R = phenyl (1(Ph)), 2-furan (1(Furan)), and 2-thiophene (1(Thio)), have been characterised. Through variation of the functionalised carboxylate group, both the one-dimensional chain structure and properties of the frameworks have been systematically modulated. The magnetic behaviour for each framework has been modelled with a zero-field splitting model and the presence of weak inter-dimer coupling was assessed.

scholarly journals Reinforcing Effect and Flame Retardancy of Aluminium Hydrate-filled Rubber

2005 ◽  
Vol 78 (11) ◽  
pp. 424-428
Author(s):  
Shigeyoshi HAYASHI ◽  
Takushi HABU ◽  
Kaneyoshi HAYASHI ◽  
Kazunori WAKAMATSU ◽  
Hisaya SATO
Keyword(s):  
Flame Retardancy ◽  
Reinforcing Effect ◽  
Filled Rubber
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