헥사메틸다이실라잔

Metals -> Metalloid Compounds (Silicon)

Corrosives

0.7741 g/cu cm at 25 °C

0.76 @25 °C

Soluble in acetone, benzene, ethyl ether, heptane, perchloroethylene

Insol in water, reacts slowly

In water, 392 mg/l @ 25 °C /Estimated/

48 °F (NFPA, 2010)

27 °C

81 °F (27 °C) closed cup

14 °C (closed cup) /from table/

125 °C

125 °C @760 [mm Hg]

13.8 [mmHg]

13.8 mm Hg at 25 °C

13.8 [mm Hg] @25 °C

This chemical does not meet GHS hazard criteria for 5.8% (35 of 606) of reports.

Danger

H225 (93.7%): Highly Flammable liquid and vapor [Danger Flammable liquids]

P210, P233, P240, P241, P242, P243, P260, P261, P262, P264, P270, P271, P273, P280, P301+P317, P301+P330+P331, P302+P352, P302+P361+P354, P303+P361+P353, P304+P340, P305+P354+P338, P316, P317, P321, P330, P361+P364, P363, P370+P378, P403+P235, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 606 reports by companies from 27 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Danger

Chemical: Silanamine, 1,1,1-trimethyl-N-(trimethylsilyl)-

Regulation (EC) No 1935/2004 (amended)

Silanamine, 1,1,1-trimethyl-N-(trimethylsilyl)- is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of Silanamine, 1,1,1-trimethyl-N-(trimethylsilyl)- are required to report information about their production and use of this chemical to the EPA under the Toxic Substances Control Act (TSCA). (40 eCFR Part 711)

Status: Active Update: 25-04-2023 https://echa.europa.eu/registration-dossier/-/registered-dossier/15274

1,1,1,3,3,3-Hexamethyldisilazane: Does not have an individual approval but may be used under an appropriate group standard

The New Jersey Worker and Community Right to Know Act requires public and private employers to provide information about hazardous substances at their workplaces. (N.J.S.A. 34:5A-1 et. seq.)

Measurements of the autoignition temperatures for several series of mono-,di-, tri- and tetra-alkylsilanes showed that the ease of oxidation decrease with increasing substitution. /Hexamethylsilazane is an/ easily ignited or pyrophoric compound.

Section 8(a) of TSCA requires manufacturers of this chemical substance to report preliminary assessment information concerned with production, exposure, and use to EPA as cited in the preamble in 51 FR 41329.

Pursuant to section 8(d) of TSCA, EPA promulgated a model Health and Safety Data Reporting Rule. The section 8(d) model rule requires manufacturers, importers, and processors of listed chemical substances and mixtures to submit to EPA copies and lists of unpublished health and safety studies. Hexamethyldisilazane is included on this list.

HEXAMETHYL DISILAZANE reacts with many carbonyl-containing organic compounds to generate gaseous ammonia. May be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen may be generated in combination with stronger reducing agents, such as hydrides.

Flam. Liq. 2 (93.7%)

Flammable liquids - Category 2

Corrosives, Flammable agents - 3rd degree, Reactive agents - 1st degree

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational exposure or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal, aquatic, and plant life; and conformance with environmental and public health regulations.

SRP: The scientific literature for the use of contact lenses in industry is conflicting. The benefit or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.

5.8 [mg/m3]

64 [mg/m3]

380 [mg/m3]

LC50 Pimephales promelas (Fathead minnow) 167 mg/L/96 hr; static

LC50 Daphnia magna (Waterflea) 186 mg/L/48 hr /Conditions of bioassay not specified in source examined/

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 390(SRC), determined from a structure estimation method(2), indicates that hexamethyldisilazane is expected to have moderate mobility in soil(SRC). Volatilization of hexamethyldisilazane from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 8.7X10-5 atm-cu m/mole(SRC), using a fragment constant estimation method(3). The potential for volatilization of hexamethyldisilazane from dry soil surfaces may exist(SRC) based upon a vapor pressure of 13.8 mm Hg(4).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 390(SRC), determined from a structure estimation method(2), indicates that hexamethyldisilazane may adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon an estimated Henry's Law constant of 8.7X10-5 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 9.9 hours and 8.9 days, respectively(SRC). The pKa of hexamethyldisilazane is 7.55(5), indicating that this compound will partially exist in cation form in the environment and cations generally adsorb more strongly to organic carbon and clay than their neutral counterparts(6). According to a classification scheme(7), an estimated BCF of 21(SRC), from an estimated log Kow of 2.6(8) and a regression-derived equation(9), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Hexamethyldisilazane is expected to hydrolyze slowly in water(5,10,11), although actual rate data for this compound were not located.

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), hexamethyldisilazane, which has a vapor pressure of 13.8 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase hexamethyldisilazane is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 18 days(SRC), calculated from its rate constant of 9.0X10-13 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3).

Section 8(a) of TSCA requires manufacturers of this chemical substance to report preliminary assessment information concerned with production, exposure, and use to EPA as cited in the preamble in 51 FR 41329.

Pursuant to section 8(d) of TSCA, EPA promulgated a model Health and Safety Data Reporting Rule. The section 8(d) model rule requires manufacturers, importers, and processors of listed chemical substances and mixtures to submit to EPA copies and lists of unpublished health and safety studies. Hexamethyldisilazane is included on this list.

Agents employed in the preparation of histologic or pathologic specimens for the purpose of maintaining the existing form and structure of all of the constituent elements. Great numbers of different agents are used; some are also decalcifying and hardening agents. They must quickly kill and coagulate living tissue.

Used to deactivate chromatography support materials and to promote adhesion of photoresists in the electronics industry; [HSDB]

Semiconductor Manufacturing [Category: Industry]

Deactivation of chromatographic support materials. In electronic industry as an adhesion promoter for photoresists on silicon.

The substance is used as a chemical intermediate in the production of siloxane polymers.

Plastics Material and Resin Manufacturing

Silanamine, 1,1,1-trimethyl-N-(trimethylsilyl)-: ACTIVE

All HMDS is sold as electronic-grade material, indicating that the level of each metal impurity is less than 1 ppm.