Dielectric Relaxation of Poly(n-butyl acrylate)

Hayakawa, Tadashi; Adachi, Keiichiro

doi:10.1295/polymj.32.845

Cited by 21 publications

(30 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The values of the activation energies (table 4) suggest that the rotational dynamics is coupled to secondary relaxation processes of PAAs. In particular, for PEA and PMA, E ∆ agrees with the activation energy of secondary β relaxation found by dielectric spectroscopy and ascribed to the dynamic of the -COOR side chain [28], while for PnBA, E ∆ coincides with the activation energy of the relaxation of the -OR group in the side-chain [29].…”

Section: Materials and Experimental Detailssupporting

confidence: 69%

Probing the cooperative dynamics varying the side-chain length of poly(alkyl acrylate)s: ESR experiments

Andreozzi¹,

Autiero²,

Faetti³

et al. 2007

Philosophical Magazine

View full text Add to dashboard Cite

The rotational dynamics of the tracer cholestane dissolved in non-entangled nearly monodisperse poly(alkyl acrylate) melts has been investigated by means of electron spin resonance spectroscopy, Three samples with almost the same molecular weight were selected, poly(methyl acrylate), poly(ethyl acrylate) and poly(n-butyl acrylate) and their linear viscoelastic properties were also characterized. Large temperature intervals were found with power laws relating shear flow relaxation and probe rotational diffusion. The main aim of this paper was the study of the sharp crossover between two different fractional regimes that for all the samples was observed at a temperature T-C = 1.15 - 1.25 T-g. The decoupling from Structural relaxation at T < T-C was ascribed to the onset of cooperative effects on the length scale probed by the tracer. These results fit in the general scenario regarding the dynamical information extractable from ESR on cholestane, a probe with its long-axis dimension greater than the typical length characterizing the rigid segment of polymers

show abstract

Section: Materials and Experimental Detailssupporting

confidence: 69%

Probing the cooperative dynamics varying the side-chain length of poly(alkyl acrylate)s: ESR experiments

Andreozzi¹,

Autiero²,

Faetti³

et al. 2007

Philosophical Magazine

View full text Add to dashboard Cite

show abstract

“…All the data locate on the line given by Equation (2). The glass transition temperature of polybutyl acrylate (PBA) is 238 K based on the Fox equation, corresponding well with the dielectric result, [19] which shows the a dielectric loss peak is in the temperature range from 230 to 270 K.…”

Section: Resultssupporting

confidence: 63%

“…For the b 0 peak of P(MMA/BA) copolymers, the apparent energy barrier decreases from 0.80 eV for PMMA to 0.72 eV for MMA(81)/BA (19) with an increase of BA mass percent in the copolymer, as shown in Fig. 5.…”

Section: Resultsmentioning

confidence: 80%

Investigation of Pendant Group and Chain Segment Motions in P(MMA/BA) Copolymers by Thermally Stimulated Depolarization Current

Zhou

Zhang

et al. 2007

Journal of Macromolecular Science, Part B

View full text Add to dashboard Cite

Poly(methyl methacrylate/butyl acrylate) [P(MMA/BA)] copolymers (M h 2 Â 10 5 ) with different mass percentages of MMA were synthesized by the method of solution polymerization. Thermally stimulated depolarization current (TSDC) technique was used to investigate the effect of copolymerization on pendant group and chain segment motions. Three TSDC peaks were observed over the temperature range from 310 to 400 K. The highest temperature, r peak originates from the detrapping of trapped charge carriers. The lower temperature, a peak corresponds to the glass transition. The activation energy of the a relaxation decreases from 1.2 eV for PMMA to 0.98 eV for MMA(75)/BA(25). In the fitting process, another peak, b 0 , is separated on the low temperature side. The apparent energy barrier of the b 0 for PMMA is 0.80 eV. The b 0 relaxation is thought to correspond to the motion of pendant groups including intraand inter-molecular interactions. All three peaks move to lower temperatures with an increase in BA component, and the activation energy for the a and b 0 relaxations also decreases with the increase of BA component in copolymers, indicating that the flexible side groups of BA have an effect of plasticization on the glass transition and motion of pendent groups. The temperatures of the a and b 0 peaks of P(MMA/BA) copolymers follow the Fox equation. Fitting results gives the a peak at 238 K and b 0 peak at 225 K for polybutyl acrylate (PBA).

show abstract

“…In the activated region IV the probe rotation could be coupled to more local modes [4,27]. In fact, the value of the activation energy of the process, DE = 4.3 ± 1.2 kJ/mol, is comparable to the barrier height between gauche and trans sites around the O-C bonds of the side chain ester group, according to a calculation carried out in [28].…”

Section: Discussionmentioning

confidence: 93%

Probing the cooperative and local modes of a poly(methyl acrylate) sample via ESR spectroscopy

Andreozzi

Autiero

Faetti

et al. 2006

Journal of Non-Crystalline Solids

View full text Add to dashboard Cite

Dielectric Relaxation of Poly(n-butyl acrylate)

Cited by 21 publications

References 14 publications

Probing the cooperative dynamics varying the side-chain length of poly(alkyl acrylate)s: ESR experiments

Probing the cooperative dynamics varying the side-chain length of poly(alkyl acrylate)s: ESR experiments

Investigation of Pendant Group and Chain Segment Motions in P(MMA/BA) Copolymers by Thermally Stimulated Depolarization Current

Probing the cooperative and local modes of a poly(methyl acrylate) sample via ESR spectroscopy

Contact Info

Product

Resources

About