• International Journal of Concrete Structures and Materials
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• 제19권1E호
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• pp.41-48
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• 2007

Addition of latex to concrete is known to increase its durability and permeability. The purpose of this study is to analyze air void systems in latex-modified concretes using a reasonable and objective method of image analysis with such experimental variables as water-cement (w/c) ratios, latex contents (0%, 15%) and cement types (ordinary portland cement (OPC), high-early strength (HES) cement and very-early strength (VES) cement). The results are analyzed by spacing factor, air volume (content) after hardening, air void distribution and structure. Additionally, air void systems and permeability of latex-modified concrete (LMC) are compared by a correlation analysis. The results are as follows. The LMC of the same w/c ratio showed better air entraining (AE) effect than OPC with AE water reducer. The VES-LMC showed that the quantity of entrained air below $100{\mu}m$ increased more than four times. For the case of HES-LMC, microscopic entrained air between the range of 50 to $500{\mu}m$ increased greater than 7 times even in the absence of anti-foamer. Although spacing factor was measured rather low, the permeability of latex-modified concrete was good. It is construed that air void system does not have a considerable effect on the property of latex-modified concrete, but latex film (membrane) has a definite influence on the durability of LMC.

• 한국응용과학기술학회지
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• 제32권1호
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• pp.72-77
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• 2015

고급지방산 메틸 에스테르류의 소포제를 합성하고 FT-IR과 $^1H-NMR$ 분석을 통해 확인하였다. FT-IR을 이용하여 합성된 물질의 특징인 -C=O기는 $1740cm^{-1}$ 부근에서, 그리고 C-O기는 $1175cm^{-1}$ 피크 값을 가지는 것을 확인하였다. 또한 $^1H-NMR$ 분석을 통해 에스테르의 -C=O의 Chemical shift가 2.29 ppm에서 나타나는 것을 확인하였다. 표면장력은 Surface Tensiometer CBVP-43을 이용하여 측정하였다. 표면장력은 17.7에서 21 dyne/cm 값을 가진다. SLS 수용액에서의 소포능은 Ross-Miles법을 통해 측정되었다. 4종류의 소포제 중 소포능은 스테아르산메틸을 이용하여 제조한 소포제가 가장 뛰어난 것으로 측정됐다.