CAS NO.：91293-60-6 N,N,N′,N′,1-Pentamethyl-1-propylsilanediamine

Frequently Asked Questions：

Q.What is N,N,N′,N′,1-Pentamethyl-1-propylsilanediamine?

A.It is an alkyl-substituted bis(dimethylamino)silane with the linear formula CH₃(CH₂)₃Si(CH₃)[N(CH₃)₂]₂ (CAS 91293-60-6, molecular formula C₇H₂₀N₂Si, MW 160.34). The silicon center carries two reactive dimethylamino groups, one methyl and one n-propyl group — the propyl chain adds organic compatibility and hydrophobicity to the products built from it.

Q.How is this product identified? Is the CAS number confirmed?

A.The product is defined by its structure and molecular formula: (Me₂N)₂Si(Me)(n-Pr), C₇H₂₀N₂Si, MW 160.34. This CAS has limited public catalog coverage, so every batch is confirmed by GC and NMR and documented on the COA. We recommend customers cross-check the structure against their synthesis requirements; we are happy to provide spectra and batch data before order confirmation.

Q.What is this product mainly used for?

A.It is used as a difunctional silylating reagent for active-hydrogen compounds and as a propyl-functional building block for polysilazanes, silicone resins, water-repellent surface treatments and custom organosilicon synthesis. The n-propyl group improves solubility/compatibility in non-polar organic systems.

Q.How does it differ from bis(dimethylamino)dimethylsilane (BDMADMS, CAS 3768-58-9)?

A. BDMADMS, (Me₂N)₂SiMe₂, has two methyl groups on silicon; this product replaces one methyl with an n-propyl group. Both have two dimethylamino leaving groups and similar silylating reactivity, but the propyl-bearing molecule incorporates a hydrophobic alkyl side chain into the resulting siloxane/polysilazane network, which is useful when organic compatibility or surface hydrophobicity is required.

Q.What purity do you supply?

A. Our standard grade is 95% min (by GC), with COA for every batch. If your application requires higher assay, controlled moisture or trace-metal limits, send us your target spec and we will quote a custom-produced batch.

Q.Are physical property data available?

A. Because this CAS has limited published reference data, we do not quote literature numbers. Each batch is characterized in-house — boiling range, density, refractive index, GC purity and moisture — and the actual values are reported on the COA so your process design uses measured data rather than estimates.

Q.How should it be stored and handled?

A. Like all bis(dimethylamino)silanes, it is highly moisture-sensitive: the Si–N bonds hydrolyze with water, liberating flammable, pungent dimethylamine. Store tightly sealed under dry nitrogen or argon in a cool, dry, dark place; transfer under inert atmosphere; use fume extraction and PPE. Full guidance is provided in the SDS.

Q. What packaging options are available?

A. Standard packaging is fluoride bottles, fluorinated / iron / plastic drums or IBC tanks according to order quantity, sealed dry under inert conditions before dispatch. Small sealed sample bottles are available for evaluation; cylinders, ampoules or custom-fitted packaging can be arranged on request.

Q. Are COA, SDS and DG documents provided? How is it shipped?

A. Yes — each batch ships with COA and SDS, and regulatory documents are available on request. As a flammable, corrosive, water-reactive aminosilane it is shipped through certified dangerous-goods channels by air, sea or courier, door to door, with complete DG documentation for customs clearance.

Q. Can I get a sample, custom specification or small-batch supply?

A. Yes. We support gram-scale samples for evaluation, custom purity/specification batches, and scale-up to production volumes. Because this is a specialty alkyl diaminosilane, we can also produce analog structures (different alkyl groups) on request. Send us your target application, grade and quantity — contact James Zhang at james.zhang@dakenchem.com for specification, price and lead time, usually within one working day.

Application Cases：

Case 1 — Propyl-Functional Polysilazane Synthesis

A silicone R&D team uses the propyl-substituted diaminosilane as a co-monomer in polysilazane preparation. Controlled ammonolysis/hydrolysis builds Si–N networks carrying propyl side chains, yielding polysilazane coatings with improved hydrophobicity and organic-resin compatibility versus all-methyl analogs.

Case 2 — Water-Repellent Surface Treatment Agent

A construction-protection formulator incorporates the reagent into silane/siloxane water-repellent treatments for mineral surfaces. The propyl group contributes low surface energy, while the two dimethylamino groups enable catalyst-free reaction with surface moisture/silanols, releasing only dimethylamine during curing.

Case 3 — Anhydrous Silylation in Fine Chemical Synthesis

A fine-chemical producer applies the reagent to silylate carboxylic acid and alcohol intermediates under strictly anhydrous conditions. Its high reactivity gives complete conversion of hindered groups, and its alkyl substitution improves the solubility of the silylated intermediates in non-polar reaction media.

Case 4 — Oxide Nanoparticle Modification for Polyolefin Composites

A materials lab treats silica filler with the propyl-functional diaminosilane to install alkyl-grafted surface layers. The treated filler shows improved dispersion in polyolefin matrices and reduced moisture uptake, supporting better mechanical and dielectric performance of the composite.

Case 5 — Custom Organosilicon Intermediate Supply

A specialty chemicals distributor orders batch quantities with NMR/GC documentation for a customer developing a novel alkyl-modified silicone resin. The defined structure (one propyl, one methyl, two dimethylamino groups on silicon) serves as a controlled branching/coupling unit in the customer’s proprietary polymer route.