Correlations between chain parameters and failure characteristics of polymers below their glass transition temperature

Fractal model of the free volume of vitreous poly(vinyltrimethylsilane) from data on gas diffusion

“…For the PVTMS and PC polymers, we have T g = 440 and 418 K [3], ϕ cl = 0.467 and 0.427 (at 293 K), C ∞ = 6.7 and 2.4 [19], S = 27.2 and 31.7 Å 2 [20], d f = 2.70 and 2.53, and D f = 4.33 and 3.13, respectively. Therefore, the higher chain flexibility of the PVTMS polymer as compared to that of the PC polymer (C ∞ = 6.7 and 2.4, respectively) is responsible for the higher dimension D f of the former polymer.…”

Temperature Dependence of the Mechanisms of Crazing and Shear in Amorphous Glassy Polymers: A Current Review and a New Approach

“…for craze fibrils [21] is where rp is the craze length (or deformation zone), 6, is the craze opening (or deformation zone). Having measured r p and 6, immediately before sample breaking, from equations 9 and 11 it is easy to estimate the maximum draw ratio in the deformation zone AD the draw ratio in craze, or in deformation zones, may be done using the relationship proposed by Donald and Kramer [4,5] In the framework of the cluster model 1, may be found from the known values of ME using the relationship between molecular mass and chain volume [28] and cross-section area of macromolecule [29], d = Se The results of such calculations of Ac and AD for PC are presented in Figure 5 by points. Their comparison with the experimental data obtained by Plummer and Donald [l 11 shows that in the crazing region the values of Ac are in a good agreement, despite the use of PC of different origin.…”

Structure and properties of particulate-filled polymer nanocomposites

“…where the characteristic relation C I is derived in accordance with Eqn (51), and the cross section area S for LDPE particles is assumed to be 14X9 A 2 [108]. The cluster network density n cl of macromolecular entanglements can be calculated as [94] n cl j cl…”