Petroleum Industrial Grade Sodium Carboxymethyl Starch (Modified Starch)

Carboxymethyl starch sodium (CMS), also known as carboxymethyl starch or industrial monosodium glutamate, is a white or yellow powder with no odor or taste.

Product Introduction:

Carboxymethyl starch sodium (CMS), also known as carboxymethyl starch or industrial monosodium glutamate, is a white or yellow powder with no odor or taste. It is non-toxic and does not easily mold. It dissolves in cold water at room temperature to form an electrolyte colloid solution. It is a water-soluble anionic polymer compound with a substitution degree greater than 0.2, which is easily soluble in water when in an alkaline environment. It is unstable in acidic conditions and easily forms free acids. It does not dissolve in organic solvents. This substance is a modified starch ether and is produced from corn starch through alkalization and etherification reactions. It should be stored in a ventilated and dry place and protected from moisture and fire.

Main Applications:

The aqueous solution of CMS is stable and has excellent properties. It has functions such as adhesion, thickening, water retention, emulsification, suspension, and dispersion. CMS is used as a mud stabilizer and water retention agent in oil well operations, helping to reduce water loss and improve the coagulation stability of clay particles in the drilling fluid. CMS has little effect on the plastic viscosity of the mud and has a significant impact on power and shear force, which is beneficial for carrying drill cuttings. Especially when drilling salt layers, it can stabilize the drilling fluid, reduce the loss volume, and prevent well wall collapse. It is particularly suitable for salt and alkali wells with high salinity and high pH values.
The most core application is as an efficient anti-filtering agent. The carboxyl groups on the molecular chain of CMS can strongly hydrate and adsorb on the well wall rock, helping to form a dense and low-permeability filter cake, effectively sealing micro-pores in the formation, significantly reducing the filtration loss of the drilling fluid, and thus stabilizing the well wall and protecting the oil and gas reservoir. It provides a certain structural viscosity, which is helpful for suspending rock cuttings and carrying drill cuttings out of the wellbore, especially in shallow well sections and low-solidity drilling fluids, with significant effects.
Compared to natural starch, its chemically modified structure significantly enhances resistance to microbial decomposition and stability under medium-low temperature conditions (typically effective temperature range can reach 120°C - 135°C). It still maintains good performance in drilling fluids containing salt (NaCl) and low-concentration calcium ions. The biodegradability of CMS is superior to many synthetic polymers (such as polyacrylamide types), and its biological toxicity is usually low. This makes it an important choice in drilling fluid formulations in environmentally sensitive areas.
Application in completion fluids and well repair fluids: Due to its low harm to the formation and good filtration loss control, it is also often used in the preparation of high-quality completion fluids, well repair fluids, and perforation fluids to minimize damage to the permeability of the oil and gas layer.