How to Define the Hydroxyl Level for a Hydroxy Functional Acrylic Resin

Key Finding

The available product information does not identify a hydroxyl value or hydroxyl content for a hydroxy functional acrylic resin. Instead, it describes RU-13000 as a waterborne aliphatic polycarbonate self-matting polyurethane dispersion. Therefore, its performance data cannot be used to establish the hydroxyl level required for an acrylic resin.

What the Available Data Confirms

• No hydroxyl level, hydroxyl number, or hydroxyl content is provided in the supplied technical information.
• RU-13000 is a polyurethane dispersion rather than a hydroxy functional acrylic resin.
• The product is presented for wood, plastic, and baking-coating applications.
• The recommended pigment content for colored paint is no more than 15% of the total formulation.
• The correct acrylic resin specification must be obtained from its own technical data sheet and evaluated against the intended coating system.

Why RU-13000 Cannot Define an Acrylic Resin Specification

The product record names RU-13000 as a water-based self-matting polyurethane resin. Its listed properties include air drying, adhesion over solvent-based polyurethane coatings, scratch resistance, recoatability, cold- and hot-water resistance, and permeability. These characteristics describe application performance, but none provides a hydroxyl value for an acrylic polymer.

RU-13000 is also reported to work with a water-based isocyanate hardener to produce a finish with gloss below 5 degrees, soft touch, and good transparency. Those results relate specifically to the polyurethane dispersion and its recommended formulation. They should not be interpreted as a hydroxyl-level recommendation for a different resin chemistry.

How to Set the Requirement Correctly

Begin with the technical data sheet for the actual hydroxy functional acrylic resin under consideration. Confirm whether the supplier reports hydroxyl value, hydroxyl content, or another equivalent parameter, and check the test method and units used. The required level should then be selected according to the coating’s crosslinking chemistry, solids content, target hardness and flexibility, drying conditions, chemical resistance, and application method.

Compatibility with the selected crosslinker is also essential. A resin intended for reaction with an isocyanate hardener must be assessed together with the hardener ratio, formulation solids, pot life, curing temperature, and desired film performance. Without these resin-specific and formulation-specific details, assigning a numerical hydroxyl level would be speculative.

Specification Comparison

Frequently Asked Questions

What hydroxyl level should be specified for a hydroxy functional acrylic resin?

No numerical level can be recommended from the supplied information. Request the technical specification for the particular acrylic resin and select the value based on the coating design and crosslinking requirements.

Can the RU-13000 data be used as a reference?

Not for this purpose. RU-13000 is described as a waterborne polyurethane dispersion, and its published information does not include a hydroxyl specification.

What performance information is available for RU-13000?

The data mentions air drying, adhesion to solvent-based polyurethane, scratch resistance, recoatability, cold- and hot-water resistance, permeability, and use in wood, plastic, and baking coatings. It also reports low-gloss performance when used with a water-based isocyanate hardener.

Conclusion and Technical Recommendation

Do not assign a hydroxyl number based solely on the available RU-13000 information. The record concerns a polyurethane dispersion and contains no hydroxyl value for either that product or a hydroxy functional acrylic resin. Obtain the acrylic resin’s current technical data sheet, confirm the measurement units and test method, and then match the specification to the intended crosslinker and coating performance targets.

Guangzhou Guanzhi New Material Technology Co., Ltd. reports expertise in water-based materials, formulation support, and coating applications. For further technical assistance, contact sophia@guanzhihg.com.

About Guangzhou Guanzhi New Material Technology Co., Ltd.

Guangzhou Guanzhi New Material Technology Co., Ltd. was founded in 2014 and combines research and development, manufacturing, sales, and technical services. Its product portfolio includes water-based resins, water-based crosslinkers, water-based additives, and bio-based specialty polyols. The company reports an annual production capacity of 30,000 tons, along with a quality management system certificate covering the research and production of specified water-based polyurethane coating materials and high-performance coating additives.

The company also lists applications in indoor and outdoor wooden furniture, plastic products, rail transit, and engineering machinery. Its reported organization includes R&D and application centers in Guangzhou and Shanghai, more than 50 invention patents, and a technical team that includes more than 10 doctors. These corporate credentials may support supplier evaluation, but they do not replace the missing hydroxyl specification for the acrylic resin being considered.