In an increasingly competitive UV and waterborne resin market, formulators face constant pressure to achieve more with fewer raw materials — high reactivity, strong adhesion, mechanical toughness, and rheology control, all without compromising water resistance or shelf stability.
SINOMER OOXEA (CAS: 115965-75-8) is a specialty oxazole-ring acrylate monomer designed to meet these demands in a single molecule. Unlike conventional hydroxyl-functional monomers such as HEA or HPA, OOXEA is built around a six-membered 1,3-oxazine heterocycle that delivers a unique combination of adhesion promotion, resin toughening, and inherent thickening — making it a versatile building block for UV-curable formulations and waterborne acrylic resin synthesis alike.
Chemical Name: 2-(2-Oxo-3-oxazolidinyl)ethyl acrylate;2-Propenoic acid, 2-(2-oxo-3-oxazolidinyl)ethyl ester
Molecular Formula: C₈H₁₁NO₄
Molecular Weight: 185.18 g/mol
The SINOMER OOXEA molecule consists of two functional domains working in synergy:
| Structural Unit | Function |
|---|---|
| Six-membered 1,3-oxazine ring (core skeleton) | Contains both O and N heteroatoms with a polar amide carbonyl group. This ring is the source of adhesion promotion, hydrolysis resistance, and resin thickening capability. |
| Terminal acrylate double bond (side chain) | Standard UV-polymerizable group that ensures efficient free-radical crosslinking and film formation. |
Key structural distinction:
Unlike hydroxyl-functional monomers (HEA, HPA, HEMA), OOXEA contains no free hydroxyl groups. After curing, it forms stable acylurea linkages that resist hydrolysis, avoiding the common weakness of hydroxyl-based monomers in hot, humid environments. Instead, the polar oxazine ring forms intermolecular hydrogen bonds with substrates such as plastics, metals, and paper — anchoring the coating at the molecular level and dramatically improving adhesion.
The oxazine ring contains N and O polar groups but no free hydroxyls. When copolymerized, it moderately enhances resin hydrophilicity and assists self-emulsification in waterborne systems — improving emulsion stability without sacrificing cured film water resistance.
Polar groups on the oxazine ring form strong hydrogen bonds with metal, plastic, and paper surfaces, creating an interfacial chemical anchor. This significantly improves adhesion to difficult substrates such as PP, nylon, and aluminum foil, reducing reliance on separate adhesion promoters.
The closed-ring oxazine skeleton is structurally stable with few hydrolyzable sites. After incorporation into the resin backbone, it enhances resistance to boiling water, acid, and alkali — overcoming the whitening and delamination issues commonly seen with hydroxyl-functional monomers.
When formulated into acrylic polymer systems, SINOMER OOXEA exhibits a pronounced performance synergy: at equivalent loading levels, mechanical strength, thermal stability, and surface scratch resistance improve simultaneously. This "small addition, multi-dimensional modification" effect enables formulators to achieve toughening + thickening + adhesion in one step, reducing the need for multiple additive packages.
In UV inks for plastic, PET, and metal substrates, OOXEA enhances interlayer adhesion and flexibility. Cured films resist cracking upon bending. In outdoor printing inks, it contributes to weatherability and yellowing resistance, offering a cost-effective alternative to higher-priced specialty adhesion monomers.
At low addition levels in acrylic UV adhesive formulations, OOXEA noticeably increases bond strength and resistance to acid/alkali corrosion. For notoriously difficult substrates such as untreated PP and nylon, the oxazine-ring hydrogen bonding substantially improves interfacial adhesion and reduces delamination failure rates. Well-suited for 3C electronics bonding and label laminating adhesives.
Thickening modification: When copolymerized into waterborne acrylic resins, OOXEA provides internal thickening — building viscosity directly into the polymer chain. This reduces or eliminates the need for external polyacrylate thickeners, avoiding the water-resistance penalty typically associated with post-added rheology modifiers.
Resin toughening: Copolymerizing OOXEA into hard waterborne acrylic resins lowers the resin glass transition temperature (Tg), imparting impact resistance and bending flexibility to cured films. This directly addresses the "brittleness problem" of many waterborne coatings. Widely used in waterborne wood coatings and industrial waterborne primer/topcoat resin synthesis.
Leveraging the modifiable functional groups on the oxazole ring, OOXEA is finding increasing R&D traction in electronic lithography auxiliary materials and pharmaceutical polymer carriers — representing a high-value growth segment for functional fine chemicals.
| Performance Dimension | What SINOMER OOXEA Delivers |
|---|---|
| Adhesion | Hydrogen-bond anchoring to PP, nylon, metals, paper — no separate adhesion promoter needed |
| Toughness | Lower Tg, impact-resistant films — solves waterborne coating brittleness |
| Thickening | Internal polymer-chain thickening — reduces external thickener loading |
| Hydrolysis resistance | Oxazine ring structure — superior boiling water and acid/alkali resistance |
| Crosslinking | Standard acrylate double bond — full UV and thermal curing compatibility |
The bottom line:
The six-membered oxazine ring plus acrylate dual functionality is the molecular logic behind OOXEA's four-in-one performance. Most conventional monofunctional monomers cannot deliver this combination. For waterborne systems, OOXEA is a scarce dual-purpose monomer — simultaneously toughening and thickening the resin while streamlining the formulation. For UV systems, small additions yield meaningful improvements in substrate adhesion and film toughness, reducing total formulation cost.
Q1: What is the CAS number of SINOMER OOXEA?
A: The CAS number is 115965-75-8. It is also referred to as an oxazole-ring or oxazine-ring acrylate monomer in technical literature.
Q2: How does OOXEA differ from HEA, HPA, or HEMA?
A: OOXEA contains no free hydroxyl groups. Instead, it features a polar oxazine heterocycle that provides adhesion and hydrophilicity without the hydrolysis sensitivity of hydroxyl-functional monomers. This means better long-term water and humidity resistance.
Q3: What is the recommended addition level in UV formulations?
A: Typically 5–20% of the total monomer/oligomer blend, depending on the substrate and performance target. For difficult plastics (PP, nylon), the higher end of this range is recommended. Always optimize through gradient testing.
Q4: Can OOXEA be used in waterborne acrylic resin synthesis?
A: Yes — this is one of its core applications. It copolymerizes into acrylic resin backbones to provide internal thickening and toughening, reducing the need for external thickeners and improving overall coating performance.
Q5: Is OOXEA compatible with standard UV photoinitiators?
A: Yes. OOXEA polymerizes via a standard acrylate double bond and is compatible with common Type I and Type II photoinitiators (e.g., 184, TPO, BDK) under both mercury lamp and LED UV sources.
Q6: Does OOXEA contribute to yellowing?
A: No. The oxazine ring structure is thermally and photochemically stable, and OOXEA is considered a low-yellowing monomer suitable for clear and light-colored formulations.
Q7: What packaging and storage conditions apply?
A: Standard packaging is 25 kg/drum or 200 kg/drum. Store in a cool, dry place away from direct sunlight and heat sources. Shelf life is typically 12 months under recommended storage conditions.
Q8: Is a sample available for testing?
A: Yes. We offer complimentary samples for technical evaluation. Contact our sales team with your application details, and we will arrange shipment.
For TDS, SDS, sample requests, or formulation guidance, contact Sinocure Chemical Group today.
