Dimethylphenylsilanol vs Silane: Procurement Data Guide
Differentiating Dimethylphenylsilylsilanol from Silane Using Physical State and Boiling Point Benchmarks
Procurement managers often encounter classification errors where Dimethylphenylsilanol is misidentified as Dimethylphenylsilane due to similar nomenclature. However, the presence of the hydroxyl (-OH) group in the organosilicon compound fundamentally alters its physical properties compared to its silane counterpart. According to NIST data, Dimethylphenylsilane (CAS 766-77-8) exhibits a boiling point of approximately 157°C and remains a liquid across standard operating temperatures. In contrast, Dimethylphenylsilanol typically presents as a crystalline solid or highly viscous liquid at room temperature due to intermolecular hydrogen bonding.
From a field engineering perspective, a critical non-standard parameter to monitor is the viscosity shift during winter shipping. While silanes maintain consistent flow characteristics, silanols may exhibit partial crystallization or significant thickening if ambient temperatures drop near their melting point. This behavior is not always captured in standard specifications but impacts pumping and dosing accuracy. The table below outlines the primary physical distinctions used for initial vendor verification.
| Parameter | Dimethylphenylsilanol | Dimethylphenylsilane |
|---|---|---|
| CAS Registry Number | 5272-18-4 | 766-77-8 |
| Functional Group | Silanol (-Si-OH) | Silane (-Si-H) |
| Physical State (25°C) | Solid / Viscous Liquid | Liquid |
| Boiling Point | Please refer to the batch-specific COA | ~157°C (NIST) |
| Molecular Weight | ~152.28 g/mol | 136.27 g/mol |
Understanding these benchmarks is essential when reviewing the high-purity organic synthesis intermediate specifications provided by suppliers.
Critical Certificate of Analysis Parameters for Verifying Silanol Hydroxyl Functionality
When auditing a Certificate of Analysis (COA), the hydroxyl value is the definitive metric for confirming silanol functionality. Standard purity assays (e.g., GC area %) may not distinguish between the silanol and its condensation products. Procurement teams should request data on water content and hydroxyl number. Trace water can accelerate the condensation of silanols into siloxanes, altering the reactivity of the chemical intermediate.
At NINGBO INNO PHARMCHEM CO.,LTD., we emphasize the importance of batch-specific testing for hydroxyl functionality to ensure consistency in downstream reactions. If the hydroxyl value deviates from the expected range, it indicates potential degradation or incomplete synthesis. Always cross-reference the COA against the purchase order specifications for hydroxyl content, not just general purity.
Technical Specifications for Bulk Packaging Requirements and Moisture Barrier Protection
Proper packaging is vital to maintain the stability of silanol derivatives. Unlike silanes, which are primarily sensitive to oxidation, silanols are highly susceptible to moisture-induced condensation. Bulk packaging must incorporate effective moisture barrier protection. Common industry standards include lined 210L drums or IBC totes with sealed valves to prevent atmospheric humidity ingress.
Logistics planning should account for temperature-controlled containers if shipping to regions with high humidity or extreme cold, mitigating the risk of crystallization or hydrolysis. We focus strictly on physical packaging integrity, such as double-sealed liners and desiccant inclusion, to preserve product quality during transit. Avoid suppliers who cannot guarantee the integrity of the moisture barrier upon arrival.
Verifying Chemical Identity via CAS Registry and Molecular Weight Metrics
The most reliable method to prevent procurement errors is verifying the CAS Registry Number. Dimethylphenylsilanol is uniquely identified by CAS 5272-18-4. Confusion often arises with Dimethylphenylsilane (CAS 766-77-8). Molecular weight verification via mass spectrometry provides a secondary check. The silanol structure includes an additional oxygen atom, resulting in a molecular weight of approximately 152.28 g/mol, whereas the silane analogue is 136.27 g/mol.
Advanced verification may involve reviewing IR spectra. The silanol group exhibits a distinct O-H stretching band that is absent in silane spectra. For detailed information on production consistency, reviewing documentation regarding the industrial synthesis route dimethylphenylsilanol scale up can provide insight into the manufacturer's capability to maintain structural integrity during production.
Evaluating Purity Grades and Impurity Profiles for Dimethylphenylsilane Contamination Risks
Incomplete reduction or hydrolysis during manufacturing can leave residual Dimethylphenylsilane in the final silanol product. This impurity profile is critical for applications requiring precise stoichiometry. Mass spectrometry investigations, such as those discussed in scientific literature regarding dissociation kinetics, highlight how methyl substitution affects fragmentation patterns. Procurement specifications should define maximum allowable limits for silane contaminants.
High levels of silane impurities can interfere with reactions designed specifically for hydroxyl functionality. For industries such as cosmetics, where sensory properties are paramount, impurity profiles must be tightly controlled. Further details on how purity affects end-use performance can be found in our analysis of sensory profile optimization in leave-on cosmetic formulations. Ensuring the absence of reducing silane impurities is key to maintaining product performance.
Frequently Asked Questions
How to identify Silanol vs Silane in vendor listings?
Check the CAS Registry Number immediately. Dimethylphenylsilanol is 5272-18-4, while Dimethylphenylsilane is 766-77-8. Additionally, verify the functional group listed in the chemical name; Silanol indicates an -OH group, whereas Silane indicates an -H group attached to silicon.
Does the physical state differ between Silanol and Silane at room temperature?
Yes. Dimethylphenylsilane is typically a liquid at room temperature with a boiling point around 157°C. Dimethylphenylsilanol often exists as a solid or viscous liquid due to hydrogen bonding between hydroxyl groups.
What packaging is required to prevent Silanol degradation?
Silanols require moisture-barrier packaging such as lined drums or IBCs with sealed valves to prevent condensation into siloxanes. Temperature control during shipping is also recommended to prevent crystallization.
Sourcing and Technical Support
Accurate identification and sourcing of Dimethylphenylsilanol require a partner with deep technical expertise in organosilicon chemistry. NINGBO INNO PHARMCHEM CO.,LTD. provides comprehensive technical support to ensure your supply chain remains secure and compliant with your specific manufacturing needs. Partner with a verified manufacturer. Connect with our procurement specialists to lock in your supply agreements.