Enhancing the ring crush index of paper and pulp molding products has long presented a challenge in the papermaking industry. In this study, (3-chloro-2-hydroxypropyl) trimethylammonium chloride was used to conduct cationic modification on bamboo powder. The positively charged quaternary ammonium groups were covalently grafted onto the bamboo powder. This cationic modified bamboo powder can be used as a reinforcing additive, which can simultaneously enhance the ring crush and tensile strength of the paper. The cationic modified bamboo powder increased the ring crush index of the paper to 16.52 N & centerdot;m & centerdot;g-1, representing a 315.08% improvement over the original paper, while the tensile strength reached 31.08 N & centerdot;m & centerdot;g-1, corresponding to a 185.40% enhancement. Furthermore, at an additive loading of 25%, the burst strength and tear strength increased by 139.76% and 188%, respectively, relative to the original paper. The cationic modified bamboo powder was subsequently applied to pulp molding products, where it also produced significant improvements in multiple physical properties. This work demonstrates a viable strategy for preparing bio-based reinforcing additives from natural materials, offering a promising pathway for advancing the high-value utilization of bamboo resources and supporting sustainable paper-based alternatives to plastics.
Veratryl alcohol ((3,4-dimethoxyphenyl)methanol) was treated with an excess amount of homoveratrol (Ho, 1,2-dimethoxy-4-methylbenzene) or creosol (Cr, 2-methoxy-4-methylphenol) under acidic conditions in aqueous 1,4-dioxane (Diox) solutions containing triflic acid with various Diox contents (defined as Ho or Cr system, respectively) to quantitatively simulate acid condensation of lignin. Five or three products were identified by LC/MS and NMR analyses in the Ho or Cr system, respectively, and three condensation products, alpha-6-type dimer, alpha-5-type dimer, and alpha-6/alpha-6-type trimer, were quantified by HPLC analysis in either system. The alpha-6-type dimer was the only major product, whereas the alpha-5-type dimer was a minor product in either system, suggesting that guaiacyl lignin has a strong regiopreference for acid condensation at the aromatic C6- over C5-carbon. The concentration ratio of the alpha-6- to alpha-5-type dimer was about 100 in the Ho systems and 11-12 in the Cr systems, the regiopreference being 8-9 times weaker in the latter. This implies that a phenolic hydroxy group at the aromatic C4-carbon markedly promotes acid condensation at the aromatic C5-carbon, the ortho-position of the aromatic C4.
Cortex Mori Radicis, which is the dried root bark of Morus alba L. from the Moraceae family, is a commonly used traditional Chinese medicine in clinical practice with multiple pharmacological activities. However, its chemical constituents are unclear. Traditional methods for chemical composition analysis, have only been able to identify a small fraction of the chemical constituents present in wood material. To comprehensively identify the chemical constituents in Cortex Mori Radicis, this study localized them based on their precursor ion features, and then performed targeted MS2 analysis for structure identification. Firstly, the chemical components isolated from Cortex Mori Radicis were analyzed to derive their precursor ion features. And then, ions extracted from the MS scan data of Cortex Mori Radicis, which match the precursor ion features, were located. After constructing the precursor ion lists, targeted MS2 analysis was performed for structure identification. This approach allowed for the identification of not only high-abundance but also low-abundance compounds. As a result, a total of 402 chemical constituents were successfully identified from Cortex Mori Radicis, and a large number of isomers of known compounds were also discovered, which provides a reference for the isolation and research of new compounds in Cortex Mori Radicis.
