Correlations involving the Mooney—Rivlin C2 constant and the number of chain atoms between physical entanglements, Nc

Boyer, Raymond F.; Miller, Robert L.

doi:10.1016/0032-3861(87)90192-3

Cited by 16 publications

(11 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…That occurs when a large number of topological constraints, other than chemical crosslinking linked to vulcanization, disrupt the ideality of the network 25. The nature of topological constraints always gives rise to debate, and the articles by Boyer and Miller26 and more recently Sherbakov and Grishin27 review this aspect. They involve either entanglement between macromolecules or physical crosslinks (van der Waals forces, etc.)…”

Section: Resultsmentioning

confidence: 99%

Comparative study of the elasticity and permeability of vulcanized films made with skim and cream natural rubber latex

Winsunthorn

Bonfils

Pochat-Bohatier³

et al. 2008

J of Applied Polymer Sci

View full text Add to dashboard Cite

The purpose of this study was to gain a clearer picture of the structure and properties of vulcanized films made with skim and cream latex from Hevea brasiliensis. The two properties targeted for this study were the elasticity of the films and their permeability to acetone. Surface characterization by atomic force microscopy revealed that vulcanization substantially modified the structure of the films compared to unvulcanized films. Unlike unvulcanized films, particle identity was retained in the vulcanized films made with cream latex, even after 4 weeks of aging. In addition, skim latex gave vulcanized films with greater elasticity than those obtained with cream latex. On the basis of the structural characterization carried out on the latex and films and information from the literature, the greater elasticity of the skim films arose from more entanglements between polyisoprene chains and associations between proteins. Despite differences in the structure, the acetone permeability was very similar for skim and cream vulcanized films.

show abstract

Section: Resultsmentioning

confidence: 99%

Comparative study of the elasticity and permeability of vulcanized films made with skim and cream natural rubber latex

Winsunthorn

Bonfils

Pochat-Bohatier³

et al. 2008

J of Applied Polymer Sci

View full text Add to dashboard Cite

show abstract

“…1 and formulated by eqn (8), l e , l r , and s R must be determined properly for all the n segments of the sample.…”

Section: Resultsmentioning

confidence: 99%

“…[6][7][8] This means that for highly swollen networks the Gaussian model can provide an adequate approximation. The stress-strain dependence of a unidirectional deformed gel sample may be expressed on the basis of eqn (1) and (2).…”

Section: Theoretical Backgroundmentioning

confidence: 99%

See 1 more Smart Citation

A novel method to determine the elastic modulus of extremely soft materials

Stirling

Zrı́nyi

2015

Soft Matter

View full text Add to dashboard Cite

Determination of the elastic moduli of extremely soft materials that may deform under their own weight is a rather difficult experimental task. A new method has been elaborated by means of which the elastic modulus of such materials can be determined. This method is generally applicable to all soft materials with purely neo-Hookean elastic deformation behaviour with elastic moduli lower than 1 kPa. Our novel method utilises the self-deformation of pendent gel cylinders under gravity. When suspended, the material at the very top bears the weight of the entire gel cylinder, but that at the bottom carries no load at all. Due to the non-uniform stress distribution along the gel sample both the stress and the resulting strain show position dependence. The cross-sectional area of the material is lowest at the top of the sample and gradually increases towards its bottom. The equilibrium geometry of the pendant gel is used to evaluate the elastic modulus. Experimental data obtained by the proposed new method were compared to the results obtained from underwater measurements. The parameters affecting the measurement uncertainty were studied by a Pareto analysis of a series of adaptive Monte Carlo simulations. It has been shown that our method provides an easily achievable method to provide an accurate determination of the elastic modulus of extremely soft matter typically applicable for moduli below 1 kPa.

show abstract

“…The short T 2 were attributed to the influence of physically or chemically crosslinked chains, medium T 2 representing chains ends or defects effects and the long relaxation times corresponding to very mobile molecules as in the sol fraction. The molecular weight between entanglements, M e , of cis‐trans polybutadiene is indicated in the literatures as equal to 4600 g/mol30, 31 that we consider as the M e value of our polymer despite the presence of OH groups in chain‐ends. Accordingly, GPC results reported on Figure 2 shows that the proportion of entangled chains in the HTPB is of about 36%.…”

Section: Resultsmentioning

confidence: 99%

Evaluation of hydroxyl terminated polybutadiene‐isophorone diisocyanate gel formation during crosslinking process

Ducruet

Delmotte

Schrodj

et al. 2012

J of Applied Polymer Sci

View full text Add to dashboard Cite

Crosslinking reaction of hydroxyl-terminated polybutadiene (HTPB)/isophorone di-isocyanate (IPDI) was monitored by infrared spectroscopy, dynamic mechanical analysis (DMA), swelling measurements, and by relaxation time (T 2 ) measurements obtained by low-field NMR technique. Chemical reaction monitored by FTIR shows that urethane bonds were predominantly formed throughout the whole reaction period while DMA and swelling became only effective once the three-dimensional network was formed. NMR results allow differentiating between relaxation-processes associated with different fractions of the reactants in the mixture prior to the network formation. The most important finding in this study is that two of the relaxation processes were found to decline whereas a new fraction with a short relaxation time which emerged specifically at an early stage of reaction and progressed along with advancement of the reaction. All results pointed out to a change in the mixture behavior around 30 h of crosslinking reaction at 60 C, reflecting an important restriction in molecules diffusion and mobilities which were attributed to the gel point formation.

show abstract

Correlations involving the Mooney—Rivlin C2 constant and the number of chain atoms between physical entanglements, Nc

Cited by 16 publications

References 53 publications

Comparative study of the elasticity and permeability of vulcanized films made with skim and cream natural rubber latex

Comparative study of the elasticity and permeability of vulcanized films made with skim and cream natural rubber latex

A novel method to determine the elastic modulus of extremely soft materials

Evaluation of hydroxyl terminated polybutadiene‐isophorone diisocyanate gel formation during crosslinking process

Contact Info

Product

Resources

About