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The purpose of this paper is to prepare microencapsulated phase change materials (PCMs) and apply them to cotton and wool fabrics for developing thermo-regulating fabrics.

Microencapsulated n-hexadecane and n-octadecane with poly(methylmethacrylate-co-2-hydroxy ethyl methacrylate) shell was prepared. Microcapsules were fabricated using oil-in-water emulsion polymerization method. Their chemical structure, microstructure, thermal energy storage properties and thermal stability were analyzed by Fourier-transform infrared spectroscopy, polarized light microscope, differential scanning calorimeter and thermogravimetric analyzer, respectively. The mean particle size was tested by a particle sized instrument. The microcapsules were applied to the wool and cotton fabrics using pad-dry-cure method. The thermo-regulating property of the fabrics was evaluated using the T-History test. The distribution and durability of the microcapsules on the fabrics was investigated with scanning electron microscopy.

Spherical microcapsules with p(MMA-co-HEMA) shell and n-alkane core have been produced successfully. n-hexadecane in microcapsule solidifies at 14.8−15.6°C with the latent heat of 65.6−129.8 J/g and melts at 16.7−16.9°C with the latent heat of 67.6−136.9 J/g. Microencapsulated n-octadecane solidifies at 25.8−26.3°C with the latent heat of 74.1−106.2 J/g and melts at 26.8−27.4°C with the latent heat of 80.3−113.4 J/g. The microcapsules have enough thermal stability to the temperature of 150°C that was applied during the fixation of microcapsules on the fabric. The thermo-regulating effect of the microcapsule-incorporated fabrics has been proved by the T-history test.

PCM microcapsules with p(MMA-co-HEMA) shell and n-hexadecane and n-octadecane core have been produced and their usage to produce thermo-regulating textiles have been proved. To determine the thermo-regulating property of the fabrics treated with these new PCM microcapsules, a T-History system has been designed.

Board committees enable boards to function effectively, as committees improve the quality of corporate governance by fulfilling specific, assigned tasks. This study aims to explore how board structure, CEO duality and audit quality are associated with board committee structure in the context of an emerging market, namely, Turkey.

The sample consisted of 122 firms listed on the Industrial Index of Borsa Istanbul for the years between 2012 and 2014, inclusive, and this yielded 366 firm-year observations. To test the hypotheses, the panel data analysis method was used, which enabled the elimination of certain problems, such as multicollinearity and estimation bias, as well as specification of the time-variant association between the predictor variables and the output variable.

Board size, board independence and firm size had a positive association with the number and size of board committees, whereas CEO duality had a negative association with the number and size of board committees. Moreover, the appointment of female members on audit and corporate governance committees was more frequent in firms that had a high proportion of women on their boards. Finally, audit quality was positively associated with the existence of risk committee, the overall diversity of board committees and the diversity of corporate governance committees.

The study is not free from limitations. It covers the time span between 2012 and 2014; thus, readers should be cautious about generalizing these results longitudinally, as a different time periods could possibly yield different results. The second limitation concerns the fact that only industrial firms were sampled; thus, these findings may not be valid in other sectors.

The paper shifts the attention of researchers from overall board structure to board committee structure. The results of the study provide insights for policymakers, boards and shareholders. Policymakers can formulate boards and committees by considering these findings. Boards can benefit from the conclusions of this study in shaping their own structure and sub-committee structures. Current and potential shareholders may find the results of the study instructive in making investment decisions.

This study investigates the factors associated with the structure of overall and specific board committees. Additionally, while most prior research on board committees has sampled firms that are domiciled in developed countries, this study examines the subject in an emerging country context, namely Turkey. Moreover, this study adds to the literature by examining the association between audit quality and board committee structure, which has been largely neglected in prior literature.