Synthesis of <scp>catechol‐conjugated</scp> chitosan and its application as an additive for cement mortar

Choi, Hoe Young; Bae, Sung‐Ho; Choi, Se‐Jin; Ko, Haye Min

doi:10.1002/bkcs.12447

Cited by 5 publications

(3 citation statements)

References 12 publications

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“…Chitosan, as a natural biopolymer, has good biocompatibility and biodegradability [4,5]. Its degradation products are non-toxic, highly adsorptive, and noncarcinogenic, and are widely used in the biomedical, wastewater treatment, flocculation, and civil engineering fields [6][7][8][9]. The previous literature [10,11] has shown that chitosan, as a polymer structure added to cement-based materials, has great application prospects in improving the early fracture toughness of cement-based materials, improving the rheological properties of cement-based materials, and regulating the heat release process of cement hydration due to the interaction between its molecular chains and the surface of cement particles.…”

Section: Introductionmentioning

confidence: 99%

Study on the Effect of Citric Acid-Modified Chitosan on the Mechanical Properties, Shrinkage Properties, and Durability of Concrete

Qin,

Wu,

Hei

et al. 2024

Materials

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As an environmentally friendly natural polymer, citric acid-modified chitosan (CAMC) can effectively regulate the hydration and exothermic processes of cement-based materials. However, the influence of CAMC on the macroscopic properties of concrete and the optimal dosage are still unclear. This work systematically investigates the effects of CAMC on the mixing performance, mechanical properties, shrinkage performance, and durability of concrete. The results indicated that CAMC has a thickening effect and prolongs the setting time of concrete. CAMC has a negative impact on the early strength of concrete, but it is beneficial for the development of the subsequent strength of concrete. With the increase in CAMC content, the self-shrinkage rate of concrete samples decreased from 86.82 to 14.52 με. However, the CAMC-0.6% sample eventually expanded, with an expansion value of 78.49 με. Moreover, the long-term drying shrinkage rate was decreased from 551.46 to 401.94 με. Furthermore, low-dose CAMC can significantly reduce the diffusion coefficient of chloride ions, improve the impermeability and density of concrete, and thereby enhance the freeze–thaw cycle resistance of concrete.

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Section: Introductionmentioning

confidence: 99%

Study on the Effect of Citric Acid-Modified Chitosan on the Mechanical Properties, Shrinkage Properties, and Durability of Concrete

Qin,

Wu,

Hei

et al. 2024

Materials

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“…A superfície da quitosana contém um grande número de grupos amino e hidroxila, que podem ser facilmente modificados para produzir uma resposta a diferentes comportamentos [27]. Aliado ao seu baixo custo, sua utilização tem sido bastante investigada no meio científico ao longo dos anos, e não só na área da construção civil em compósitos cimentícios [28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43], como também em outras aplicações, tais como, na medicina [44,45], na agricultura [46,47] e cosméticos [48,49].…”

Section: Introductionunclassified

Concreto de cimento Portland dopado com quitosana: propriedades mecânicas e microestrutural

Silva

et al. 2023

Matéria (Rio J.)

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RESUMO A construção civil exerce função importante no consumo de energia em todo o mundo e influência, de forma significativa, o consumo total de recursos naturais e as emissões de CO2. A utilização de materiais renováveis está intrinsecamente relacionada à pesquisa e à inovação. A reutilização, a reciclagem, bem como o desenvolvimento de novos materiais e a descoberta de novas aplicações para materiais renováveis já conhecidos, podem contribuir de maneira expressiva para o desenvolvimento sustentável. A quitosana (CS) é um biopolímero com uma estrutura química e características únicas aliadas à sua farta disponibilidade como derivado da quitina, fazem com que suas possibilidades de aplicação nos mais diferentes campos tecnológicos, tenha se expandido consideravelmente. No presente trabalho, a utilização da quitosana para produção de concretos por meio de teores ótimos é investigada. Os valores de quitosana incorporados na dosagem foram 0,1%; 0,3% e 0,4%, com relação à massa de cimento. Os diferentes concretos obtidos foram submetidos a ensaios de propriedades mecânicas e microestrutural. Os resultados mostraram que a microestrutura foi favorecida com a utilização da quitosana. Bem como, apresentaram resultados favoráveis à incorporação dos teores utilizados de quitosana (se desatacando as amostras com 0,1% de substituição), sendo positivos quanto às propriedades mecânicas para a maioria das técnicas utilizadas, o que indica fortemente que a quitosana pode ser considerada como material promissor a ser incorporado na produção de concreto.

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“…Modification of the R 3 position, the primary amine, has been extensively used for synthesizing DA derivatives . Various functional molecules were conjugated at this site through amide-bond-forming reactions. − However, the conjugation to the R 3 position prevents indole formation, which is another key intermediate for surface coating; thus, the coating efficiency is not as high that compared to DA. , The indole formation inhibition may be due to the decrease in nitrogen nucleophilicity. The nitrogen in amides is less nucleophilic than that in free amines because of the nitrogen lone pair resonance stabilization by the carbonyl group.…”

Section: Introductionmentioning

confidence: 99%

Effect of N-Methylation on Dopamine Surface Chemistry

et al. 2022

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Dopamine (DA) surface chemistry has received significant attention because of its applicability in a wide range of research fields and the ability to graft functional molecules onto numerous solid surfaces. Various DA derivatives have been newly synthesized to identify key factors affecting the coating efficiency and to advance the coating system development. The oxidation of catechol into quinone followed by internal cyclization via the nucleophilic attack of primary amine is crucial for DA-based surface coating. Thus, it is expected that the amine group’s nucleophilicity control directly affects the coating efficiency. However, it has not been systematically investigated, and most studies have been conducted with the focus on the transformation of amines into amides, despite such approaches decreasing the coating efficiency; the nitrogen in amides is less nucleophilic than that in free amines. In this study, we investigated the effect of N-alkylation on dopamine surface chemistry. N,N-Dimethyldopamine (DMDA) was newly synthesized, and the coating efficiency was systematically compared with DA and N-methyldopamine (MDA). DA N-monomethylation improved the coating rate by increasing the nitrogen nucleophilicity, whereas N,N-dimethylation dramatically decreased the DA surface coating property. In addition, MDA remained capable of universal surface coating and secondary reactions using the surface catechols. This study provides opportunities for developing coating materials with advanced functions and an improved coating rate.

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Synthesis of catechol‐conjugated chitosan and its application as an additive for cement mortar

Cited by 5 publications

References 12 publications

Study on the Effect of Citric Acid-Modified Chitosan on the Mechanical Properties, Shrinkage Properties, and Durability of Concrete

Study on the Effect of Citric Acid-Modified Chitosan on the Mechanical Properties, Shrinkage Properties, and Durability of Concrete

Concreto de cimento Portland dopado com quitosana: propriedades mecânicas e microestrutural

Effect of N-Methylation on Dopamine Surface Chemistry

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