Reaction of Hexamethyldisilazane with silica / water

Reaction of Hexamethyldisilazane with silica:

Researchers have been made to study the reaction of Hexamethyldisilazane (HMDS) with OH groups with silica that can be examined by infrared spectroscopy method. This reaction frees the OH groups and results in kinetics. The reaction produces mainly hexamethydisiloxane (HMDSO) and ammonia with a small quantity of nitrogen and methane. When temperature is maintained lower than 300°C no methane is produced. Moreover, ammonia is the first product produced and subsequently HMDSO is produced. As the temperature increases, the amount of nitrogen produces increases and that of ammonia and HMDSO decreases. Reaction of pendant silyl groups with surface acidic hydroxyls to eliminate methane and the concentration of residual silyl moieties on the silica surface both increase with temperature of reaction.

HMDS is used for deactivating materials that support in gas chromatography by many Hexamethyldisilazane Makers. Kinetic studies have been made to get comprehension about the reaction of HMDS with silica and the optimum conditions in which the reactions take place the best.

Study of HMDS:

Four important chemical properties have been deduced from such studies- 1) The freely vibrating hydroxyl groups can occur in either in Si-OH or [Si-(OH)2] configurations, 2) The freely vibrating hydroxyl groups are monoenergetic (i.e. all the OH groups show the same reactivity), 3) Due to the monoenergetic nature of the OH groups, physical absorption results in same fraction of the hydroxyl group being covered for a given pressure and temperature, and 4) The mutually H-bonded OH groups on the surface are essentially nonreactive towards the various bonding agents.

Another such study outlines the kinetics for the reaction of HMDS with silica which is mainly a two-steps process. The first step is a rate determining step that produces trimethylsilylation on the surface of silanol and forms trimethylaminosilane. The second step is where a trimethylaminosilane reactive intermediate reacts to form a trimethylsilyl surface chemical and ammonia. This two step process was mainly applied to analyze the data of the kinetics of HMDS reaction with smoked silica in the field of spectroscopy.

Absorbs Techniques:

Hexamethyldisilazane reacts with many substrate surfaces to enhance their adhesive power. When HMDS reacts with the substrate, it absorbs the excess water in them, reduced surface energy and increases the photoresist adhesion on the surface. The silizane components bond with the oxygen-atoms of the substrates and the methyls offer hydrophobic layers that have good wetting and adhesive characteristics. This dehydration reaction of HMDS on wafers (semiconductor slices) is carried out using two techniques: Liquid Priming and Vapor Priming. It is commonly know that HMDS is very sensitive to the presence of water and degrades in humid air. Studies have been made to understand the reaction of HMDS in dry and humid air in the presence of absorbent surfaces. Studies show that HMDS hydrolyzes in humid air and produces trimethylsilanol (TMS) and ammonia (NH3). Chemcon Speciality Chemicals.Pvt.Ltd is suppliers and Manufacturers of of Speciality Chemicals.

An Overview of the Chemical Manufacturing Industry and HMDS Manufacturers

HMDS manufacturers

Chemicals like HMDS and Chloromethyl Isopropyl Carbonate play a crucial role in the pharmaceutical industries because they act as great intermediates that power important manufacturing processes. The pharma intermediate industry is becoming bigger and better due to the emergence of companies like Chemcon Specialty Chemicals. Chemcon is one of the most prominent HMDS Manufacturers that have changed the market significantly. Besides HMDS, the company also specializes in manufacturing Chloromethyl Isopropyl Carbonate which is a colorless and clear liquid with a molecular formula C5H9ClO3.

Performance of HMDS

For understanding the role and significance of these chemicals better, it is important to go through an entire overview of the industry and the top HMDS manufacturers, which have regained pace after a long period of recession. Various manufacturers are responsible for producing complex chemicals like HMDS in this interlinked yet self-sufficient industry. These specialty chemicals are nothing but chemical products which are sold not on the basis of their composition but their function or performance. These can be chemical formulations or single entities based on their requirements. Due to the fact that manufacturing complex chemicals like CMIC and HMDS requires special innovation and technology, the emergence of players like Chemcon has proved to be a boon for the industry.

Even though this industry is undergoing a huge transition, one important fact which has emerged is that several Japanese, Western European and North American companies are dominating the market. However, with several economic barriers being broken down, the growth of technology and presence of trade liberalization, more and more companies are entering the market to break the monopoly. As a result, specialty chemicals like Chloromethyl Isopropyl Carbonate and HMDS are now being sold at affordable rates. In Asia too, several Indian and Chinese HMDS manufacturers have entered the industry and are doing exceedingly well. As more and more competition increases, it seems that the clients will be in a win-win situation because the costs will be lower and the quality of these specialty chemicals will keep on improving.

In the last decade or so, the growth in the specialty chemical industry has been particularly low, however the profitability has been decent considering the fact that there has been a very competitive environment. The growth, which has been predicted for the upcoming future, looks to be somewhere around 2.0% which is not bad at all. The fact that all the new manufacturing firms are coming up with better technology and tools such as driers, reactors and condensers, the growth is surely going to be better by the next decade.

Uses of HMDS in Different Section

Various segments in the specialty chemicals industry are predicted to grow faster than the average growth speed. Some of these segments include: electronic chemicals, oil field chemicals, radiation curable coatings and specialty polymers. Popular chemical manufacturer like Chemcon also specializes in oil field chemicals and therefore the prospects of the company look really good from the onset.

It wouldn’t be wrong to say that the prospects of the specialty chemicals industry growing look very good not just in certain parts of the world, but the growth seems to be equally divided across the world. In no time, the world will see many more HMDS manufacturers coming up and giving tough competition to the firms having a monopoly in the market.