Qiangli Chemical Product Manual (Latest)

Differences in Dimethyl Silicone Oil Produced from DMC and Linear Oligomers The DMC route is the mainstream industrial production route in China, while the linear oligomer route is a low-cyclic, high-quality route. The core differences lie in raw material structure and polymerization mechanism. Neither route is absolutely superior; selection depends on your target specifications.

Under conventional production and identical devolatilization conditions: silicone oil produced via the DMC route has far higher cyclic content than that manufactured by the linear oligomer route.

High-purity dimethyl silicone oil (PDMS, polydimethylsiloxane), also known as methyl silicone oil, is most commonly used for cleaning Teflon (PTFE) belts. Typical grades include QL-200 series from Qiangli Chemical. This type of silicone oil is also recommended for lubrication and maintenance after cleaning, with low to medium viscosity products of 50–350 cSt generally selected.

Can dimethyl silicone oil be dispersed in methanol without floating oil? Key difference: Density of methanol ≈0.79 g/cm³; conventional dimethyl silicone oil (50‑1000 cSt) has a density of 0.96~0.97 g/cm³. ✅ No floating oil appears on the liquid surface; yet the oil phase will settle at the bottom of the container to form a bottom oil layer, which is totally different from the "floating‑oil" phenomenon in water.

The core advantage of insulating heat‑dissipating silicone oil lies in the balance between high dielectric strength and stable thermal conductivity. When selecting products, priority shall be given to five key indicators: application scenario, viscosity, dielectric strength, thermal conductivity and operating temperature.

Important premise: Conventional dimethyl silicone oil is non‑reactive silicone. It does not take part in curing and cross‑linking reactions of phenolic resin and only achieves physical blending. Its compatibility with phenolic resin is limited; the typical dosage is 0.1‑1.0 wt%. Excessive addition will cause blooming and exudation as well as degraded mechanical properties.

Silicone oils for polyester threads (PET threads) are mainly divided into three categories: base silicone oils, modified silicone oils and specialty silicone waxes. Different categories are suitable for different process stages and performance requirements. Below is the detailed classification and application guide:

Dimethicone Copolyol, also known as dimethylsiloxane‑ethylene glycol copolymer, is a class of polyether‑modified organosilicon surfactants. It is formed by introducing polyoxyethylene (PEG) and/or polyoxypropylene (PPG) side chains or end‑groups onto the polydimethylsiloxane (PDMS) backbone. It combines the hydrophobicity and lubricity of siloxanes with the hydrophilicity and water‑solubility of polyethers, exhibiting unique amphiphilic properties.

Core Conclusions: Both silicone oils fall within the low‑surface‑tension range (18‑35 mN/m), markedly lower than water (72 mN/m). Dimethicone has a lower baseline value (19‑22 mN/m). Amino‑modified amino silicone oil shows slightly higher surface tension (20‑35 mN/m, typical value: 20‑25 mN/m), yet possesses better amphiphilicity and substrate‑adsorption capacity.