Skin Conditioning

Hydrolyzed Silk Pg-Propyl Methylsilanediol

INCI: HYDROLYZED SILK PG-PROPYL METHYLSILANEDIOL

Reviewed by Rosie · Last updated 2 Jun 2026

A silicone-silk hybrid that conditions and smooths both skin and hair

Best For Skin Types

All, Dry, Mature

Addresses

Dryness, Hydration

Usage Frequency

Daily

What Is Hydrolyzed Silk Pg-Propyl Methylsilanediol?

Hydrolyzed Silk PG-Propyl Methylsilanediol is a hybrid conditioning agent that combines hydrolyzed silk proteins with a silicone derivative. Silk proteins are derived from the cocoon of the silkworm and broken down into smaller molecular fragments, which are then chemically bonded to a propyl methylsilanediol backbone — a silicone-based structure that enhances stability and spreadability.

This ingredient functions as both a skin and hair conditioner. It deposits a thin film onto the skin surface that can improve texture, reduce friction, and help the stratum corneum (outer layer) retain moisture more effectively.

How It Works

The hydrolyzed silk component adheres to the skin surface and is rich in amino acids, which can interact with the natural moisturising factor (NMF) already present in the stratum corneum. This interaction helps reinforce the skin's water-holding capacity.

The silicone portion provides a semi-occlusive barrier — not fully waterproof, but substantive enough to reduce evaporation and create a smooth, soft-feel finish. The combination allows the ingredient to both nourish and protect the outer skin layer.

Clinical Evidence & References

Published research specifically on this hybrid molecule is limited. Most evidence comes from studies on hydrolyzed silk proteins and silicones in isolation, both of which are well-established as safe conditioning agents with mild moisturising properties.

In-vitro and sensory studies suggest that silk-derived ingredients can improve skin smoothness and reduce water loss, whilst silicones are known to provide a protective, slip-enhancing layer. The combination is likely to be additive in these effects, though controlled clinical trials on this specific ingredient would strengthen the evidence base.

How to Use

This ingredient is typically used in rinse-off products (cleansers, conditioners) and leave-on formulations (serums, moisturisers, primers) at low concentrations. In leave-on products, start with formulations containing this ingredient at 1% or below to assess how your skin responds; it should feel soft and conditioned rather than heavy or occlusive. If used in multiple products, monitor for any signs of product buildup.

Safety & Precautions

Generally well-tolerated and considered safe for use in cosmetics. Silicones and hydrolyzed proteins are established ingredients with a low risk of irritation or sensitisation. Those with silicone sensitivity should patch-test before use.

Frequently Asked Questions

From the Clinic

Not sure what your skin actually needs?

Two minutes, a few questions, and we’ll point you at what matters — no guesswork.

Take the skin quiz

Learn More About Skincare Ingredients

Explore our comprehensive ingredient glossary to understand what's in your products.

Browse All Ingredients

Authorised Stockist

Official UK retailer

Tracked Delivery

Free UK shipping over £50

5 Star Rating

Trusted by thousands

Expert Advice

Free consultations