Grafted carbon fibers and their physico-chemical properties. Part IV: Grafting of cyano-biphenyl containing liquid-crystalline monomers onto modified carbon fibers

Selimović, M.; Bismarck, Alexander; Pfaffernoschke, Matthias; Springer, Jürgen

doi:10.1002/(sici)1521-4044(19990401)50:4<156::aid-apol156>3.0.co;2-5

Cited by 9 publications

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, if one is aiming to covalently attach polymeric coatings or interlayers to carbon fiber surfaces, there are only three methods available: plasma polymer deposition [12][13][14][15][16][17], electropolymerization or -deposition [8][9][10][11]18], and in situ chemical grafting reactions [19][20][21][22][23][24]. In earlier studies, we showed that it is possible to tune the carbon fiber chemistry and functionality and thereby their surface properties, i.e., hydrophilic/ hydrophobic character, by grafting suited monomers such as methacrylic acid (MAA) [25], 2-(N,N-dimethylamino) ethyl methacrylate (DMAEMA) [26] and various liquid crystalline monomers [27,28] onto carbon fibers via simple free radical bulk polymerization in the presence of the carbon fibers. The degree of grafting onto the surfaces can be adjusted by the amount of initiator used [29].…”

Section: Introductionmentioning

confidence: 99%

Polystyrene-grafted Carbon Fibers: Surface Properties and Adhesion to Polystyrene

Bismarck

Pfaffernoschke

Springer

et al. 2005

Journal of Thermoplastic Composite Materials

View full text Add to dashboard Cite

It is highly desirable to improve attractive interactions between carbon fibers and unreactive thermoplastic matrices to the possible maximum. This could be achieved by a simple grafting process to create a covalently bonded interface or interlayer, which should result in cohesive interactions between the polymer-grafted fibers and the same matrix material, leading to a better adhesion strength in the obtained composite material. Here, we are describing the grafting of styrene onto unmodified and unsized carbon fibers via free-radical bulk polymerization in the presence of fibers. After grafting, the surface properties of the carbon fiber *Author to whom correspondence should be addressed. E-mail: a.bismarck@imperial.ac.uk approach those of pure polystyrene which was proven by contact angle and zeta (-) potential measurements. As indicated by the water contact angle, the carbon fiber surface becomes more hydrophobic. Scanning electron microscopy (SEM) provides evidence of grafted polymer. This simple procedure results in a continuous polystyrene coating. The fiber diameter increases significantly after polymer grafting. The adhesion and fracture behavior between the original and polystyrene-grafted carbon fibers to a polystyrene (VESTYRON Õ ) matrix was characterized using the single-fiber pull-out test. There is a considerable increase in the measurable adhesion, i.e., the interfacial shear strength IFSS , by almost 300% between the grafted fibers and polystyrene as compared to untreated original fibers. Two planes of interfacial failure could be distinguished; first in the fiber coating interface leading to lower interfacial shear strength and second in the PS-matrix-PS-coating interphase resulting in a higher interfacial shear strength. In addition to the improved adhesion, there are also clear differences in the pull-out behavior between the nongrafted and grafted fibers. After the initial debonding process corresponding to the maximal pull-out force is completed, the pull-out force is increasing again.

show abstract

Section: Introductionmentioning

confidence: 99%

Polystyrene-grafted Carbon Fibers: Surface Properties and Adhesion to Polystyrene

Bismarck

Pfaffernoschke

Springer

et al. 2005

Journal of Thermoplastic Composite Materials

View full text Add to dashboard Cite

show abstract

Prediction of long‐term service performance of polymeric materials from short‐term tests: Creep and prediction of the stress shift factor of a longitudinal polymer liquid crystal

Akinay

Brostow

Maksimov

2001

Polymer Engineering & Sci

View full text Add to dashboard Cite

The material studied is a longitudinal polymer liquid crystal (PLC). The creep behavior of the PLC is examined in the region of nonlinear viscoelasticity. The creep compliance D curves at nine different stress (T levels, from 10 to 50 J.cm3 at a constant temperature are determined and shifted along the log time axis for uRf = 10 J .to produce the D versus t/a, master curve. A fairly general formula for stress shift factor a , , based on free volume vf and the chain relaxation capability (CRC) derived by one of the authors is applied. The formula predicts values that agree with the experimental ones within the limits of the experimental accuracy. Thus, experiments at several stress levels can serve for prediction of longterm behavior from short-term tests. The same value of the Doolittle constant B is obtained separately from temperature shift and stress shift experiments for the PLC.

show abstract

Surface modification and grafting of carbon fibers: A route to better interface

Raphael

Namratha

Chandrashekar

et al. 2018

Progress in Crystal Growth and Characterization of Materials

View full text Add to dashboard Cite

Grafted carbon fibers and their physico-chemical properties. Part IV: Grafting of cyano-biphenyl containing liquid-crystalline monomers onto modified carbon fibers

Cited by 9 publications

References 0 publications

Polystyrene-grafted Carbon Fibers: Surface Properties and Adhesion to Polystyrene

Polystyrene-grafted Carbon Fibers: Surface Properties and Adhesion to Polystyrene

Prediction of long‐term service performance of polymeric materials from short‐term tests: Creep and prediction of the stress shift factor of a longitudinal polymer liquid crystal

Surface modification and grafting of carbon fibers: A route to better interface

Contact Info

Product

Resources

About