Chitosan is a biodegradable natural polymer which is safe and non-toxic and used in different applications. Grafting of chitosan with aniline derivatives is an important route to improve its properties. Chitosan has different active groups that can be blocked in the grafting process, which could be confirmed by calculation studies. The author thinks that the confirmation of chitosan active group included in the grafting by calculations is not given before. So authors give evidence to the direction of grafting and mechanism. Poly(2-methylaniline) (P2-MA), poly(2-hydroxyaniline) (P2-HA) and their copolymers are used in the present study. Quantum mechanics calculations using density functional theory were applied to study the grafting process. The obtained data reveal that grafting occurs at NH2 groups, which is less energetic (2.04). This conclusion confirms the experimental studies. Computational calculations show that the interaction between chitosan and both P2-MA and P2-HA takes place at the NH2 group of chitosan with high stabilization energy (− 1346.7746). A complete next-to-leading order (NLO) values show that the graft could be a better candidate for NLO application (42.25 kcal mol−1) global properties (hardness). Also, the grafting process gives high reactive products due to a decrease in band gap energy.

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2-取代苯胺与壳聚糖接枝共聚的密度泛函理论计算

壳聚糖是一种可生物降解的天然聚合物，安全无毒，可用于不同的应用领域。壳聚糖与苯胺衍生物的接枝是改善其性能的重要途径。壳聚糖具有不同的活性基团，可以在接枝过程中被阻断，这可以通过计算研究得到证实。笔者认为之前没有给出计算确认接枝中包含的壳聚糖活性基团。所以作者给出了嫁接方向和机制的证据。本研究中使用了聚（2-甲基苯胺）（P2-MA）、聚（2-羟基苯胺）（P2-HA）及其共聚物。使用密度泛函理论的量子力学计算被应用于研究接枝过程。获得的数据表明接枝发生在能量较低的 NH2 基团上 (2.04)。这一结论证实了实验研究。计算表明，壳聚糖与 P2-MA 和 P2-HA 之间的相互作用发生在壳聚糖的 NH2 基团上，具有高稳定能 (- 1346.7746)。完整的次前序 (NLO) 值表明接枝物可能是 NLO 应用 (42.25 kcal mol-1) 整体特性（硬度）的更好候选者。此外，由于带隙能量的降低，接枝过程会产生高反应性产物。25 kcal mol−1) 全局特性（硬度）。此外，由于带隙能量的降低，接枝过程产生了高反应性产物。25 kcal mol−1) 全局特性（硬度）。此外，由于带隙能量的降低，接枝过程产生了高反应性产物。