Developments of the spin labelling study of polymers at interfaces

Hommel, H.

doi:10.1016/j.cis.2008.02.001

Cited by 14 publications

(8 citation statements)

References 117 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The M b and p values can also be estimated from other reports based on different techniques for probing related phenomena. The p curves obtained based on MDSC,9 electron spin resonance (ESR),34, 37, 38 and ATR22 are illustrated in Figure 8 for PMMA as a comparison with the present results. For MDSC, the data were calculated (from M b of 1.3 mg m −2 ).…”

Section: Discussionsupporting

confidence: 54%

Bound fractions of methacrylate polymers adsorbed on silica using FTIR

Krisanangkura¹,

Packard²,

Burgher³

et al. 2010

J Polym Sci B Polym Phys

View full text Add to dashboard Cite

The H-bonding of carbonyl groups on a series of methacrylate polymers with silanols on fumed silica was studied with transmission FTIR. The set included poly(alkyl methacrylates) with alkyl groups, (n-C n H 2nþ1 ) of n ¼ 1, 2, 4, and 12 and poly(benzyl methacrylate). Shifts in the vibrational frequencies for bound carbonyl groups (of $20 cm À1 lower than those found in the bulk) were observed in the adsorbed polymer samples. A series of samples with different adsorbed amounts (varying from 0.5 to 2.0 mg m À2 ) of each polymer was prepared to determine the effect of the side chain on the H-bonding. The fractions of bound carbonyls, p, for each of the methacrylate polymers studied, were calculated from a model based on the ratios of the absorption coefficients of the bound to free carbonyl resonances,The X values were determined from linear regressions of the ratios of the free to bound carbonyl intensities as a function of the amounts of adsorbed polymer, M t . The bound fractions, p, were observed to decrease with increase in adsorbed amounts and with increase in the lengths of the side chains of the methacrylate polymers, except for poly(lauryl methacrylate) (PLMA). PLMA has a very low glass transition temperature (T g ) and is likely rubbery on the surface, whereas the other polymers are likely glassy at ambient temperature.

show abstract

Section: Discussionsupporting

confidence: 54%

Bound fractions of methacrylate polymers adsorbed on silica using FTIR

Krisanangkura¹,

Packard²,

Burgher³

et al. 2010

J Polym Sci B Polym Phys

View full text Add to dashboard Cite

show abstract

“…Some experimental techniques, such as, spectroscopic ellipsometry, neutron and x‐ray reflectometry, and positron lifetime spectroscopy have been used to study the local structure or thickness changes in the polymer layer. Other studies based on NMR, ESR and FTIR have been successful in studying such interfaces. These techniques are very sensitive to the small amounts of material on the surfaces and have been used to examine the dynamics and segmental heterogeneity of the bound polymer .…”

Section: Introductionmentioning

confidence: 99%

Thermal Properties of PMMA on Silica Using Temperature‐Modulated Differential Scanning Calorimetry

Khatiwada

Hetayothin

Blum

2013

Macromolecular Symposia

View full text Add to dashboard Cite

Summary The behavior of an amorphous polymer, poly(methyl methacrylate) (PMMA), adsorbed on silica was studied using temperature‐modulated differential scanning calorimetry (TMDSC). A two‐component model, based on loosely‐bound polymer with a glass transition temperature (Tg) (similar to that of the bulk polymer) and a tightly‐bound polymer (with a Tg higher than that of the loosely‐bound polymer) was used to interpret the thermograms. Increased sensitivity allowed the two transitions in the thermograms to be quantified much more accurately than in previous work. Linear regression analysis of the ratio of the area under two transitions with composition yielded the amount of tightly bound polymer, m″B = 1.21 +/− 0.21 mg PMMA/m2silica. Two methods of analyzing the thermograms, fitting with a Gaussian‐Lorentzian (GL) cross distribution function and perpendicular drop (PD) method, yielded similar results for the amount of tightly‐bound polymer on the surfaces with the GL method having a statistically better fit to the model. The ratio of heat capacity increments of loosely bound and tightly bound polymer, ΔCpA/ΔCpB, around the glass transition, indicated the relative mobility of the two components. It was found that the ΔCpA was aboutthree times as large as that of ΔCpB suggesting that the tightly bound polymer had a much smaller change in mobility through glass transition region.

show abstract

“…The interfaces formed by polymers grafted on silica continue to be of high interest for both practical and fundamental reasons. [1][2][3][4][5] Polymers adsorbed or grafted on the surface of a solid contribute by their behavior to strongly modify the properties of this surface. Less information is available for interfaces with short grafted polymeric chains.…”

Section: Introductionmentioning

confidence: 99%

“Pseudo solid” nuclear spin echo study of poly(ethylene oxide) grafted on silica. Comparison with magic‐angle spinning technique results

Tajouri

Mariem

Hommel

2015

Concepts Magnetic Resonance

View full text Add to dashboard Cite

The polymer/solid interface of Poly (ethylene oxide) (PEO) grafted on silica is studied by 1H NMR. For grafted polymers, the dipolar interaction is an important factor in the spin–spin relaxation process. For this purpose, the part of the dipolar interaction that is not averaged to zero by the motion is used. The “pseudo solid” spin echo can indeed give an estimation of the nonzero average dipolar interactions. The appropriate pulse sequence permits a standard measurement of the average dipolar spin coupling involved in the transverse magnetization relaxation. The influence of some major parameters such as molecular weights of the chains, grafting ratios, and temperatures on the relaxation and ultimately on the concentration is followed by “pseudo solid” spin echo. The magic‐angle spinning technique is also used. The sample rotation confirms by the narrowing of the central line and the appearance of side bands, the existence of a residual dipolar interaction which reveals the concentration of high monomer units at the surface. The study of the side bands permits to calculate the second moment as a function of temperature. A fair agreement is obtained by these two independent techniques: pseudo solid echo and magic‐angle spinning.

show abstract

Developments of the spin labelling study of polymers at interfaces

Cited by 14 publications

References 117 publications

Bound fractions of methacrylate polymers adsorbed on silica using FTIR

Bound fractions of methacrylate polymers adsorbed on silica using FTIR

Thermal Properties of PMMA on Silica Using Temperature‐Modulated Differential Scanning Calorimetry

“Pseudo solid” nuclear spin echo study of poly(ethylene oxide) grafted on silica. Comparison with magic‐angle spinning technique results

Contact Info

Product

Resources

About