Influence of the chemical structure of different carboxymethylcelluloses on the performance of clay dispersions

Abstract

The aim of this work was to evaluate the influence of the chemical structure of carboxymethylcellulose (CMC) on the rheological performance and fluid loss of clay dispersions. The dispersions were prepared with a fixed content of bentonite clay (15 g/350 mL of water) and different concentrations of CMCs (0.5, 1.0, 2.0 g/350 mL of water). After aging for 24 h in ambient and static conditions, the dispersions were tested in a viscometer. Apparent and plastic viscosities, yield point and gel strength were obtained using the viscometer, according to Petrobras' standard (EP-1EP-00011-A). The filtrate volume was determined using the API filter press. The results showed that the addition of long chain, low degree of substitution and lower substitution uniformity of CMC contribute to the flocculation phenomenon. In addition, the different chemical characteristics of CMC only influence fluid loss when the ionic strength of the dispersion is set to any other value than zero.Este trabalho teve como objetivo avaliar a influência da estrutura química da carboximetilcelulose (CMC) no desempenho reológico e de perda de filtrado de dispersões de argila. As dispersões foram preparadas com concentração fixa de argila bentonítica (15 g/350 mL de água) e diferentes concentrações de CMCs (0,5, 1,0, 2,0 g/350 mL de água). Após repouso de 24 h, as dispersões foram testadas e com um viscosímetro foram calculadas as viscosidades aparente e plástica, o limite de escoamento e a força gel segundo norma da Petrobras (EP-1EP-00011-A) e o volume de filtrado foi determinado em filtro-prensa API. Os resultados evidenciaram que a adição de CMC com cadeia longa, baixo grau de substituição e menor uniformidade de substituição contribui para o fenômeno de floculação. Além disso, as diferentes características químicas do CMC somente influenciam a perda de filtrado quando a força iônica da dispersão é diferente de zero. Palavras-chave: carboximetilcelulose, desempenho, argila bentonítica, características químicas.

Fabrication of solid polymer electrolyte based on carboxymethyl cellulose complexed with lithium acetate salt as Lithium‐ion battery separator

“…Increasing the DP of a CMC polymer will also increase the molecular weight ( M v ). Thus, both can be determined through intrinsic viscosity measurements 48 . Determining the DP and M v is crucial in polymer‐based research as it can affect the physical and chemical properties of products that use the polymer as a base material.…”

“…Thus, both can be determined through intrinsic viscosity measurements. 48 Determining the DP and M v is crucial in polymer-based research as it can affect the physical and chemical properties of products that use the polymer as a base material. According to Shrivastava, 49 both values can determine the characteristics of CMC, including its mechanical stability, viscosity, polarity, chemical resistance, and thermal stability.…”

An Investigation on the Potential of Cellulose for Soil Stabilization

“…The XRD of 0.50% NaCMC treated soil imitated a similar trend of soil, inferring that no new chemical compounds formed with the reaction of soil and clay minerals. However, the anionic nature of NaCMC tends to attract the hydrated clay surface, resulting in intermolecular hydrogen bonds that enhance the strength [56]. Hence, the overall XRD analysis of soil (Figure 8) indicates the presence of silicon dioxide at peaks of 27.1 • and vaterite (a polymorph of calcium carbonate) at peaks of 21.1 • , 51.1 • and 68.7 • .…”