Mechanical and dynamical mechanical properties of chloroprene rubber and cellulose II composites

2004 ◽  
Vol 92 (4) ◽  
pp. 2425-2430 ◽  
Author(s):  
Agnes F. Martins ◽  
Sergio M. de Meneses ◽  
Leila L. Y. Visconte ◽  
Regina C. R. Nunes

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1085
Author(s):  
Patricia Castaño-Rivera ◽  
Isabel Calle-Holguín ◽  
Johanna Castaño ◽  
Gustavo Cabrera-Barjas ◽  
Karen Galvez-Garrido ◽  
...  

Organoclay nanoparticles (Cloisite® C10A, Cloisite® C15) and their combination with carbon black (N330) were studied as fillers in chloroprene/natural/butadiene rubber blends to prepare nanocomposites. The effect of filler type and load on the physical mechanical properties of nanocomposites was determined and correlated with its structure, compatibility and cure properties using Fourier Transformed Infrared (FT-IR), X-ray Diffraction (XRD), Thermogravimetric Analysis (TGA) and rheometric analysis. Physical mechanical properties were improved by organoclays at 5–7 phr. Nanocomposites with organoclays exhibited a remarkable increase up to 46% in abrasion resistance. The improvement in properties was attributed to good organoclay dispersion in the rubber matrix and to the compatibility between them and the chloroprene rubber. Carbon black at a 40 phr load was not the optimal concentration to interact with organoclays. The present study confirmed that organoclays can be a reinforcing filler for high performance applications in rubber nanocomposites.



Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1510
Author(s):  
Marek Pöschl ◽  
Shibulal Gopi Sathi ◽  
Radek Stoček ◽  
Ondřej Kratina

The rheometer curing curves of neat natural rubber (NR) and neat chloroprene rubber (CR) with maleide F (MF) exhibit considerable crosslinking torque at 180 °C. This indicates that MF can crosslink both these rubbers via Alder-ene reactions. Based on this knowledge, MF has been introduced as a co-crosslinking agent for a 50/50 blend of NR and CR in conjunction with accelerated sulfur. The delta (Δ) torque obtained from the curing curves of a blend with the addition of 1 phr MF was around 62% higher than those without MF. As the content of MF increased to 3 phr, the Δ torque was further raised to 236%. Moreover, the mechanical properties, particularly the tensile strength of the blend with the addition of 1 phr MF in conjunction with the accelerated sulfur, was around 201% higher than the blend without MF. The overall tensile properties of the blends cured with MF were almost retained even after ageing the samples at 70 °C for 72 h. This significant improvement in the curing torque and the tensile properties of the blends indicates that MF can co-crosslink between NR and CR via the Diels–Alder reaction.



2012 ◽  
Vol 53 (4) ◽  
pp. 744-751 ◽  
Author(s):  
J.L. Vilas ◽  
J.M. Laza ◽  
C. Rodríguez ◽  
M. Rodríguez ◽  
L.M. León


2014 ◽  
Vol 87 (2) ◽  
pp. 360-369 ◽  
Author(s):  
Junping Zheng ◽  
Jin Tan ◽  
Hong Gao ◽  
Chuanzeng Wang ◽  
Zhilei Dong

ABSTRACT To satisfy some special demands of many applications in the fields of aerospace and the electronic industry, low temperature resistant and high electrical insulation chloroprene rubber (CR) was prepared by blending pristine CR with different weight ratios of butadiene rubber (BR). The low temperature resistance, electrical insulation properties, and mechanical properties of CR/BR blends were investigated. With increasing BR content, the low temperature resistance and electrical insulation properties were improved, whereas the tensile strength and elongation at break decreased. For the CR/BR (65/35) blend, filled with SiO2, the brittleness temperature (Tb) was reduced to −61 °C and the high electrical insulation properties were obtained without sacrificing mechanical properties too much. The tan δ plots of CR/BR blends, investigated by dynamic mechanical analysis, also revealed that BR could reduce glass transition temperature (Tg) and improve low temperature resistance of CR. The phase contrast microscope images of CR/BR blends demonstrated that the phase structure of the blends changed with increasing BR content. Furthermore, the fracture surfaces of CR/BR blends, observed by scanning electron microscopy, showed that the compatibility of CR/BR blends was poor although the CR/BR blends were homogeneous in macrostructure.



Author(s):  
Jérémy Astruc ◽  
Michel Grandbois ◽  
Gaétan Laroche ◽  
Mathieu Robert ◽  
Said Elkoun

Cellulose nanocrystals or nanoparticles (CNCs) has drawn a lot of attention due to their abundance, biocompatibility, renewability and their excellent mechanical properties paving the way to innovative and sustainable applications. In the present work, the stem residues of Asclepias Syriaca, better known as milkweed and generally regarded as a weed, was used for the first time to extract CNCs with a crystalline structure type-II (CNCs-II). Structural, thermal, morphological and mechanical properties of extracted CNCs-II were characterized by means of Fourier Transform Infrared (FT-IR), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS), Thermogravimetric Analysis (TGA) and Atomic Force Microscopy (AFM). Asclepias Syriaca stem fibers revealed quite similar cellulose content as compared to other milkweed species and, stable suspensions made of nanosphere- and nanorod- shape CNCs-II were successfully extracted from raw milkweed fibers. In addition, after conversion from cellulose-I to cellulose-II by mercerization, milkweed cellulose-II exhibited higher thermal resistance as compared to cellulose-I with degradation temperature at 328 °C and 310 °C respectively. Finally, the transversal elastic modulus of individuals CNCs-II, as measured by atomic force microscopy, was found to be in the range of 3.5-27 GPa which is consistent with reported values for CNCs-I or -II in the literature.



2011 ◽  
Vol 84 (4) ◽  
pp. 474-481
Author(s):  
P. Predeep ◽  
S. Najidha

Abstract Conducting polymers are finding new application areas in energy storage devices, optoelectronics, actuators etc. Iodine doped semiconducting prevulcanized natural rubber latex (RVNRL) is a potential candidate for many such applications. We had already demonstrated for the first time that pre-vulcanized NR latex can be doped by iodine to become electrically conducting and doping process is not affecting the flexibility or processability of the films. Synthesis and characterization of intrinsically electric conducting preculcanized natural rubber latex are briefly discussed. Further, dynamical mechanical properties of these doped RVNRL are reported. The glass transition (Tg) temperature of the chemically doped polyisoprene material was found to be shifted to higher temperature region with the iodine concentration. However, the mechanical properties are found to decrease at higher concentration of the dopant after showing an increasing trend as in the case of Tg at lower doping levels. An effort has also been made to explain this visibly contradictory behavior.



2014 ◽  
Vol 87 (2) ◽  
pp. 219-238 ◽  
Author(s):  
Roberto Todeschini ◽  
Viviana Consonni ◽  
Davide Ballabio ◽  
Andrea Mauri ◽  
Matteo Cassotti ◽  
...  

ABSTRACT In this preliminary study, mathematical models based on Quantitative Structure Property Relationships (QSPR) were applied in order to analyze how molecular structure of chloroprene rubber accelerators relates to their rheological and mechanical properties. QSPR models were developed in order to disclose which structural features mainly affect the mechanism of vulcanization. In such a way QSPR can help in a faster and more parsimonious design of new chloroprene rubber curative molecules. Regression mathematical models were calibrated on two rheological properties (scorch time and optimum cure time) and three mechanical properties (modulus 100%, hardness, and elongation at break). Models were calculated using experimental values of 14 accelerators belonging to diverse chemical classes and validated by means of different strategies. All the derived models gave a good degree of fitting (R2 values ranging from 84.5 to 98.7) and a satisfactory predictive power. Moreover, some hypotheses on the correlations between specific structural features and the analyzed rheological and mechanical properties were drawn. Owing to the relatively small set of accelerators used to calibrate the models, these hypotheses should be further investigated and proved.



1997 ◽  
Vol 16 (1) ◽  
pp. 7-18 ◽  
Author(s):  
S.N. Goyanes ◽  
G.M. Benites ◽  
J.J. González ◽  
G.H. Rubiolo ◽  
A.J. Marzocca


2011 ◽  
Vol 239-242 ◽  
pp. 1601-1604 ◽  
Author(s):  
Xiao Xue Liao ◽  
Hai Sheng Tan ◽  
Ming Chao Luo ◽  
Bing Tang ◽  
Shuang Quan Liao ◽  
...  

The effects of the ratios of natural rubber latex (NRL)and chloroprene rubber latex(CRL) and the type of compatibilizer on physical and mechanical properties of latex film were researched.The oil resistance of vulcanized latex film was tested. The compatibility of the latex blends was also analyzed by TG/DTG method.The results showed that properties of latex film were best when ratio of NRL/CRL was 75/25. As the CRL content increased, oil resistance of latex film was improved. Epoxidized natural rubber latex improved compatibility of NRL and CRL blends.



1994 ◽  
Vol 30 (9) ◽  
pp. 1025-1028 ◽  
Author(s):  
Valéria Gonçalves Costa ◽  
Regina Célia Reis Nunes


Sign in / Sign up

Export Citation Format

Share Document