Compatibility Investigations on Polymer‐Fiber‐Reinforced Cements Modified with Polymer Latexes

Abstract

Summary: In construction, polymer fibers are commonly applied beside steel, glass and mineral fibers to improve material's flexibility to shear stress. As in other composite systems, there are compatibility problems present between the fibers and the cement due to the different chemical natures and the different thermal expansion coefficients of the cement and the polymers. Within this study the interactions between two Portland cements and polymer fibers were investigated by SEM and solid‐state NMR spectroscopy. To improve the wetting ability of the polymer fibers by the cement matrix, redispersible latex powders were successfully applied to improve the adhesion between the cement matrix and the fibers. Within this study, several solid‐state nuclear magnetic resonance (NMR) spectroscopy methods, detecting 1H, 13C, 27Al and 29Si nuclei, and scanning electron microscopy (SEM) were applied. Thus, cement pastes, inorganic additives and organic admixtures could be monitored individually.SEM images of the interface between poly(propylene) fibers and Portland cement, hardened and hydrated in the presence of a 2 wt.‐% poly[(vinyl acetate)‐co‐ethylene] latex.magnified imageSEM images of the interface between poly(propylene) fibers and Portland cement, hardened and hydrated in the presence of a 2 wt.‐% poly[(vinyl acetate)‐co‐ethylene] latex.

Solid state NMR analysis of poly(L‐lactide) random copolymer with poly(ε‐caprolactone) and its reactive extrusion process

“…2 Especially, in the field of textiles, research using solid state NMR has become increasingly extensive in recent years, since the mechanical and thermal properties of textile fibers are significantly affected by high-order structure and morphology of their material. 3,4 It is also well known that the mechanical properties of a fiber depend on the motion of its polymer molecules. For study of molecular motion with solid state NMR, relaxation time analysis is the most popular method, since the relaxation time, which reflects the molecular motions, dynamically changes with molecular composition and production process.…”

Diminished cartilage‐lubricating ability of human osteoarthritic synovial fluid deficient in proteoglycan 4: Restoration through proteoglycan 4 supplementation

“…The use of solid state NMR as a characterization method is expected to expand to a wide range of polymer science because it does not require any destructive sample treatments 2. Especially, in the field of textiles, research using solid state NMR has become increasingly extensive in recent years, since the mechanical and thermal properties of textile fibers are significantly affected by high‐order structure and morphology of their material 3, 4. It is also well known that the mechanical properties of a fiber depend on the motion of its polymer molecules.…”

Pull‐out behavior of polymer fibers in concrete

“…Materials such as steel, polymers or inorganic materials have been investigated in different sizes and surface modifications. [5][6][7][8][9][10] Polymer fibers, for instance polypropylene (PP) fibers are of high interest, due to their easy handling, good workability and high economic impact. [11][12][13] Despite their beneficial effects, the main problem with PP fibers is the poor adhesion between the fiber and the matrix.…”