scholarly journals Novel Polyvinyl Alcohol/Styrene Butadiene Rubber Latex/Carboxymethyl Cellulose Nanocomposites Reinforced with Modified Halloysite Nanotubes

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Yanjun Tang ◽  
Dingding Zhou ◽  
Junhua Zhang

Novel polyvinyl alcohol (PVA)/styrene butadiene rubber (SBR) latex/carboxymethyl cellulose (CMC)/halloysite nanotubes (HNTs) nanocomposites were successfully prepared through physical blending. The as-obtained PVA/SBR/CMC/HNTs nanocomposites were coated on the surface of old corrugated container (OCC)-based paper in an effort to improve the mechanical properties of paper. To improve the dispersion of HNTs and enhance the compatibility between HNTs and polymer matrix, HNTs were modified with titanate coupling agent (TCA). FT-IR, together with TGA, confirmed that TCA was grafted onto the surface of HNTs successfully. XRD demonstrated that the crystal structures of HNTs remained almost unchanged. TEM showed that modified HNTs exhibited good dispersion and possessed nanotubular structures with an outer diameter of around 50 nm and an inner diameter of about 20 nm. SEM gave an indication that modified HNTs were dispersed more uniformly than unmodified HNTs within PVA/SBR/CMC matrix. Rheological measurement exhibited that surface modification process enhanced the compatibility between HNTs and polymer matrix, thus resulting in the decreased viscosity of nanocomposites. In comparison with unmodified HNTs, modified HNTs were found to contribute more to the enhancement in mechanical properties, which might be attributed to the better dispersion and compatibility of modified HNTs evidenced by TEM, SEM, and rheological measurement.

Polymers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 883 ◽  
Author(s):  
Jing Lin ◽  
Dechao Hu ◽  
Yuanfang Luo ◽  
Bangchao Zhong ◽  
Yongjun Chen ◽  
...  

Vulcanization and reinforcement are critical factors in governing the ultimate practical applications of elastomer composites. Here we achieved a simultaneous improvement of curing and mechanical properties of elastomer composites by the incorporation of a functionalized halloysite nanotubes–silica hybrid (HS-s-M). Typically, HS-s-M was synthesized by 2-mercapto benzothiazole (M) immobilized on the surface of halloysite nanotubes–silica hybrid (HS). It was found that the HS-s-M uniformly dispersed in the styrene-butadiene rubber (SBR) matrix, offering more opportunity for M molecules to communicate with rubber. In addition, the physical loss of accelerator M from migration and volatilization was efficiently suspended. Therefore, SBR/HS-s-M composites showed a lower curing activation energy and a higher crosslinking density than SBR/HS composites. Moreover, a stronger interfacial interaction between HS-s-M and SBR was formed by the cross-linking reaction, giving a positive contribution to the eventual mechanical properties. The possible vulcanization and reinforcement mechanisms of SBR/HS-s-M composites were also analyzed in detail.


2021 ◽  
Vol 11 (9) ◽  
pp. 1453-1465
Author(s):  
Fang Xu ◽  
Heng Li ◽  
Tao Sun ◽  
Yu Zhou ◽  
Jing Zhu ◽  
...  

This study investigated three types of fly ash-based geopolymer mortar (FAG) modified with polyvinyl alcohol fiber (PVA) or styrene butadiene rubber (SBR) latex, where the influence of PVA fibers and SBR latex on the mechanical properties and durability of FAG were studied. The sample performance was subsequently interpreted by characterizing the microstructures of modified FAG samples via the use of scanning electron microscopy (SEM), where the internal structural stress and modification mechanisms were clarified by microstructural analysis. The results showed that the incorporation of PVA fibers mainly promotes the mechanical properties of the samples, especially the early flexural strength, and alleviates their dry shrinkage. However, adding SBR latex to the geopolymer mortar damages the compressive strength and increases the dry shrinkage of samples while improving their freeze-thaw resistance and 28-day flexural strength. The results also show that FAGs have great sulfate resistance. Microstructural analysis reveals that while the dehydrated SBR latex is capable of forming a continuous porous film structure, the fibers also facilitate the formation of a three-dimensional network structure between the dense FAG gels; thus, a more stable geopolymer structure is formed, resulting in an improvement in the toughness and durability of the samples. Furthermore, the SBR latex promotes tight connections between the fibers and geopolymer matrix so that the bond strength between the interfacial transition zone (ITZ) is greatly enhanced.


Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 519
Author(s):  
Vitalii Bezgin ◽  
Agata Dudek ◽  
Adam Gnatowski

This paper proposes and presents the chemical modification of linear hydroxyethers (LHE) with different molecular weights (380, 640, and 1830 g/mol) with the addition of three types of rubbers (polysulfide rubber (PSR), polychloroprene rubber (PCR), and styrene-butadiene rubber (SBR)). The main purpose of choosing this type of modification and the materials used was the possibility to use it in industrial settings. The modification process was conducted for a very wide range of modifier additions (rubber) per 100 g LHE. The materials obtained in the study were subjected to strength tests in order to determine the effect of the modification on functional properties. Mechanical properties of the modified materials were improved after the application of the modifier (rubber) to polyhydroxyether (up to certain modifier content). The most favorable changes in the tested materials were registered in the modification of LHE-1830 with PSR. In the case of LHE-380 and LHE-640 modified in cyclohexanol (CH) and chloroform (CF) solutions, an increase in the values of the tested properties was also obtained, but to a lesser extent than for LHE-1830. The largest changes were registered for LHE-1830 with PSR in CH solution: from 12.1 to 15.3 MPa for compressive strength tests, from 0.8 to 1.5 MPa for tensile testing, from 0.8 to 14.7 MPa for shear strength, and from 1% to 6.5% for the maximum elongation. The analysis of the available literature showed that the modification proposed by the authors has not yet been presented in any previous scientific paper.


Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2413
Author(s):  
Mariapaola Staropoli ◽  
Vincent Rogé ◽  
Enzo Moretto ◽  
Joffrey Didierjean ◽  
Marc Michel ◽  
...  

The improvement of mechanical properties of polymer-based nanocomposites is usually obtained through a strong polymer–silica interaction. Most often, precipitated silica nanoparticles are used as filler. In this work, we study the synergetic effect occurring between dual silica-based fillers in a styrene-butadiene rubber (SBR)/polybutadiene (PBD) rubber matrix. Precipitated Highly Dispersed Silica (HDS) nanoparticles (10 nm) have been associated with spherical Stöber silica nanoparticles (250 nm) and anisotropic nano-Sepiolite. By imaging filler at nano scale through Scanning Transmission Electron Microscopy, we have shown that anisotropic fillers align only in presence of a critical amount of HDS. The dynamic mechanical analysis of rubber compounds confirms that this alignment leads to a stiffer nanocomposite when compared to Sepiolite alone. On the contrary, spherical 250 nm nanoparticles inhibit percolation network and reduce the nanocomposite stiffness.


2021 ◽  
pp. 096739112110313
Author(s):  
Ahmed Abdel-Hakim ◽  
Soma A el-Mogy ◽  
Ahmed I Abou-Kandil

Blending of rubber is an important route to modify properties of individual elastomeric components in order to obtain optimum chemical, physical, and mechanical properties. In this study, a novel modification of styrene butadiene rubber (SBR) is made by employing acrylic rubber (ACM) to obtain blends of outstanding mechanical, dynamic, and oil resistance properties. In order to achieve those properties, we used a unique vulcanizing system that improves the crosslink density between both polymers and enhances the dynamic mechanical properties as well as its resistance to both motor and break oils. Static mechanical measurements, tensile strength, elongation at break, and hardness are improved together with dynamic mechanical properties investigated using dynamic mechanical analyses. We also proposed a mechanism for the improvement of crosslink density and consequently oil resistance properties. This opens new opportunities for using SBR/ACM blends in oil sealing applications that requires rigorous mechanical and dynamic mechanical properties.


Author(s):  
Koushik Pal ◽  
Soumya Ghosh Chowdhury ◽  
Dipankar Mondal ◽  
Dipankar Chattopadhyay ◽  
Sanjay Kumar Bhattacharyya ◽  
...  

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