# Agricultural Residues of Lignocellulosic Materials in Cement Composites
## 3 Results and Discussion
[11], extractives hinder cement curing and the interactions between lignocellulosic particles and the cement matrix, thus leading to empty spaces between the matrix and the lignocellulosic particles/fibres. Coconut shell had high levels of extractives (39.07%). In that case, the extractives may act as a barrier to satisfactory linkage between the particles and cement, but may be necessary to allow the treatment to achieve better composite properties [1]. Ash in lignocellulosic materials is the material remaining after incineration has removed the organic constituents [37]. Thus, the ash fraction comprises most of the inorganic substances present in the native substrate [38]. A higher amount of ash was observed in banana pseudostem, owing to its high mineral content. The same result has been found by [PERSON] et al. [8]. According to [PERSON] et al. [6], holocellulose has a significant influence on the composite properties through the concentration of hemicellulose dissolved due to the higher alkalinity of the cement's hydration water. Hemicellulose can diminish the composite's resistance because it is one of the elements responsible for adherence between fibrils of the plant material and the arrangement of fibrils within the cement matrix. Table 1 shows large differences among the chemical compositions of the lignocellulosic material residues evaluated. The variation in the proportions of the chemical constituents is influenced by the plant species; agricultural variables, such as soil quality, weathering conditions, the level of plant maturity, and the quality of the retting process; and measurement conditions that may include or exclude moisture [39]. Consequently, these factors may affect the physical and mechanical properties of the panels produced from those materials. Table 2 shows the values obtained for the length, diameter, and slimmess index of the lignocellulosic materials used as reinforcement for cement-based panels. Banana fibres had the highest length and diameter values. However, the highest slimmess index and intermediate lengths were observed for coconut fibres. Coconut had the smallest diameter. Eucalyptus, sugarcane bagasse, and coffee husk showed the closest geometric characteristics, achieving the lowest values of length and intermediate diameters. The geometric characteristics of the lignocellulosic materials directly influence the fibre/matrix interface. These characteristics allow for adequate covering and can increase the mechanical resistance of the produced panel; alternatively, they can generate a loss of interaction, which can increase the \begin{table}
\begin{tabular}{c c c c c} \hline
**Lignocellulosic Materials** & **Length (cm)** & **Diameter (cm)** & **Slimness Index** & **Density (g/cm3)** \\ \hline Eucalyptus & 0.27 c (0.07) & 0.07 b (0.01) & 3.81 bc (0.96) & 0.341 a (0.092) \\ \hline Sugar cane & 0.29 c (0.06) & 0.05 c (0.01) & 6.10 bc (1.54) & 0.094 d (0.005) \\ \hline Banana pseudostem & 1.25 a (0.12) & 0.18 a (0.03) & 7.41 b (1.40) & 0.237 b (0.008) \\ \hline Coconut shell & 0.64 b (0.17) & 0.03 d (0.01) & 21.93 a (9.46) & 0.138 c (0.087) \\ \hline Coffee husk & 0.19 c (0.03) & 0.08 b (0.02) & 2.50 c (0.69) & 0.167 c (0.007) \\ \hline \(p\) value & 0.0000 & 0.0000 & 0.0000 & 0.0024 \\ \hline CV (\%) & 25.09 & 26.29 & 61.74 & 6.31 \\ \hline \end{tabular}
\end{table} 
Table 2: Averages and standard deviations of the geometry and density properties of the lignocellulosic composites. number of pores, owing to curving or even folding inside the cement matrix, thus directly affecting the physical and mechanical properties of the composites produced [6; 9]. The density values of the different types of lignocellulosic materials are shown in Table 2. There was a higher density for eucalyptus fibres (0.341 g/cm\({}^{3}\)) and a lower density for cane fibres (0.094 g/cm\({}^{3}\)). Table 3 shows the physical properties of the composites produced with the lignocellulosic materials.