ROPAQUE OPAQUE POLYMER

Ropaque Opaque Polymer is used in industrial / OEM coatings.
Ropaque Opaque Polymer is used for paper coatings / coated paper (as an opacifier/pigment).
Ropaque Opaque Polymer is used as primers, tint bases, and mid-tone formulations (to reduce TiO₂ load).

CAS Number: Mixture (proprietary formulation – individual polymeric components do not have a unique CAS number)
EC Number: Not assigned (mixture)

Chemical Nature: ROPAQUE™ is a copolymer mixture, it does not have a fixed molecular formula like a pure compound.
*Methyl methacrylate (MMA)
*Butyl acrylate (BA)
*Methacrylic acid (MAA)
*Styrene (in some grades)

Approximate repeating unit composition of the polymer backbone can be represented as:  (C₅H₈O₂)x (C₄H₈O₂)y (C₅H₈O₂)z,
Average molecular weight (Mw) of the polymer blend 50,000 – 500,000 g/mol

SYNONYMS:
ROPAQUE Opaque Polymer, ROPAQUE™ Ultra Opaque Polymer, ROPAQUE™ Ultra-E Opaque Polymer, ROPAQUE™ OP-96 Opaque Polymer, ROPAQUE™ OP-62 Opaque Polymer, ROPAQUE™ Ultra EF (Ammonia-free Opaque Polymer), Ropaque Hollow Sphere Pigment, Ropaque Opaque Polymer Emulsion, Ropaque OP Series, Hollow Polymer Pigment, Opaque Polymer Dispersion, Ropaque HP-91, Ropaque Ultra, Ropaque AF-1355, Ropaque OP-96

Ropaque Opaque Polymer is a hollow-sphere polymeric pigment that allows paint manufacturers to reduce the raw material cost of their formulations with no performance penalties.
Ropaque Opaque Polymer expands the boundaries of light scattering technology, providing the most efficient dry hiding in interior and exterior coatings.

In addition to providing the most efficient dry-hiding properties, Ropaque Opaque Polymer offers wide range benefits in interior and exterior paint formulations.
Ropaque Opaque Polymer (also called “opaque polymer”, “hollow latex”, “hollow-sphere polymer pigment”) is a class of polymeric opacifiers (not conventional pigments) used to improve opacity / hiding in coatings and related systems by light scattering rather than absorption.

The key structural concept of Ropaque Opaque Polymer: each particle is a hollow sphere (shell + void).
The sphere is initially water-filled; after film formation, the water diffuses out and leaves an air void inside the polymer shell.
Because air has a refractive index quite different from the polymer matrix, this void acts as a scattering center, increasing optical hiding.

To maximize scattering (i.e. maximize efficiency), two parameters are crucial: particle diameter (size of the hollow spheres) and void fraction (the internal volume of air relative to shell).
Because Ropaque Opaque Polymer shell is non-film-forming (i.e. these particles don’t themselves form a continuous film), they act as extenders / scattering centers embedded in the binder matrix rather than contributing binder strength themselves.

This mechanism of “air voids inside polymer particles for light scattering” is sometimes described under the general polymer‐science term Hohllatex (German for “hollow latex”), which is a known technique in coatings / paper industries for partial replacement of TiO₂ and other opacifiers.

USES and APPLICATIONS of ROPAQUE OPAQUE POLYMER:
Ropaque Opaque Polymer is used as an opacity-enhancing additive and TiO₂ extender in:
Architectural Paints: Ropaque Opaque Polymer improves hiding power and whiteness in interior and exterior paints.

Paper Coatings: Ropaque Opaque Polymer enhances brightness and opacity in coated paper and board.
Industrial Coatings: Ropaque Opaque Polymer is used in coatings where low density and light scattering are desirable.
Adhesives and Sealants: Ropaque Opaque Polymer provides opacity and viscosity control.

Textile Coatings: Ropaque Opaque Polymer is used in formulations requiring opacity with flexibility.
Architectural coatings (paints) use of Ropaque Opaque Polymer: interior and exterior paints (flat through high gloss).
Ropaque Opaque Polymer is used in industrial / OEM coatings.

Ropaque Opaque Polymer is used for paper coatings / coated paper (as an opacifier/pigment).
Ropaque Opaque Polymer is used as primers, tint bases, and mid-tone formulations (to reduce TiO₂ load).
Ropaque Opaque Polymer is used premium to quality interior/exterior flat through high gloss architectural paints.

ADDITIONAL BENEFITS / PERFORMANCE ADVANTAGES of ROPAQUE OPAQUE POLYMER:
Here are more nuanced benefits and performance characteristics that Ropaque Opaque Polymer types aim to deliver (or challenges that are mitigated):

*TiO₂ savings / cost reduction
Because TiO₂ is among the most expensive raw materials in white and tinted coatings, replacing even a fraction (10–35 %) with Ropaque Opaque Polymer (keeping equivalent opacity) can yield significant cost savings.
In satin/semi-gloss paints, Ropaque Opaque Polymer can replace ~20 % TiO₂; in flat coatings, ~35 % replacement is claimed in some formulations.

*Low binder demand
The spherical, non-porous nature of the particles results in lower binder absorption / demand compared to many filler/extender pigments.
This helps maintain film integrity, especially at higher pigment volume concentration (PVC).

*Tint retention, gloss & finish stability
Because these particles can scatter light without introducing strong color bias, they support good tinting behavior and stable gloss / sheen properties.

*Exterior durability enhancements
In exterior coatings, use of Ropaque Opaque Polymer can lead to improved dirt pickup resistance, better tint retention (less fading), and longer lasting opacity.

*Latency in formulation flexibility
Ropaque Opaque Polymer can allow formulators more flexibility in balancing extenders, binders, pigments, and cost—particularly in mid-tone, primer, and low-PVC systems where conventional opacifiers are less effective.

*Lower VOC / cleaner formulation potential
Some Ropaque Opaque Polymer variants (e.g. Ultra-E) are ammonia-free and suitable for low-odor, low-VOC formulations, aiding environmental / indoor air quality targets.

KEY CHARACTERISTICS / DESIGN CONSIDERATIONS of ROPAQUE OPAQUE POLYMER:
When using Ropaque Opaque Polymer / hollow-sphere polymer opacifiers, several critical design and formulation considerations must be kept in mind to preserve performance:

*Shell integrity is crucial: 
If the hollow spheres collapse (e.g. due to solvent swelling, intense shear, or plasticizer attack), the void is lost and hiding efficiency drops.
Thus, Ropaque Opaque Polymer must be robust.

*Solvent compatibility limits: 
Ropaque Opaque Polymer particles are vulnerable to solvents whose solubility parameters approach that of the polymer shell (e.g. aromatic solvents, plasticizers, white spirits) — these can soften or partially dissolve the shell, risking collapse.
Some variants of Ropaque Opaque Polymer (e.g. Dual Opaque) are more solvent-resistant.

*Optimizing particle size / void fraction: 
As mentioned, there is an optimum size (~0.38–0.40 µm) and void fraction (high, ~40+ %) for maximum light scattering.

*Deviations reduce efficiency.
Reformulation necessity: Replacing TiO₂ with ROPAQUE demands adjustments in extenders, binder levels, dispersants, coalescents, and thickeners.
The suggested approach often is to treat Ropaque Opaque Polymer as a “pigment + polymer shell” and rebalance other components accordingly.

*Critical Pigment Volume Concentration (CPVC): 
In coatings, there is a threshold of pigment content beyond which film integrity degrades.
Ropaque Opaque Polymer allows some extension beyond that threshold if used carefully, but excessive total PVC can harm film durability.

*Mixing / shear sensitivity: 
Harsh shear or mixing may damage the hollow spheres; thus, moderate mixing is recommended.
Over-shearing should be avoided. (Implicit in technical docs)

*Storage / sedimentation: 
Because these are dispersions, sedimentation or settling is a risk; periodic agitation or mixing in storage is advised to maintain uniformity.

*Film formation / drying behavior: 
The timing and mechanism of water diffusion from the hollow spheres, coalescence of the binder, and film consolidation must be well matched to avoid defects (void collapse, cracking, poor adhesion).

CHEMICAL NATURE of ROPAQUE OPAQUE POLYMER:
Ropaque Opaque Polymer is a synthetic, waterborne hollow-sphere polymer (an acrylic copolymer) made from several monomers — typically:
*Methyl methacrylate (MMA)
*Butyl acrylate (BA)
*Methacrylic acid (MAA)
*Styrene (in some grades)
These are polymerized in water via emulsion polymerization, forming hollow microspheres stabilized by surfactants and dispersants.

ADVANTAGES of ROPAQUE OPAQUE POLYMER:
Significantly increased light scattering efficiency while maintaining paint performance.
Greater cost savings while providing equal hiding.

BENEFITS of ROPAQUE OPAQUE POLYMER:
*Hollow-sphere polymeric pigment.
*Ammonia neutralized.
*Increased light scattering efficiency while maintaining paint performance.
*Cost savings by reducing level of TiO2 while providing equal hiding.
*Ropaque Opaque Polymer expands the boundaries of light scattering technology.
*Providing the most efficient dry hiding in interior and exterior coatings.
*Additionally, this non-film-forming synthetic pigment, Ropaque Opaque Polymer, is specially engineered to improve the economics of waterborne coatings while maintaining coating performance.

BENEFITS / ADVANTAGES / KEY CHARACTERISTICS of ROPAQUE OPAQUE POLYMER:
*Efficient light scattering / hiding: 
Because of the hollow-sphere structure, Ropaque Opaque Polymer can scatter light effectively, contributing to opacity and hiding in coatings without requiring as high a loading of TiO₂.

*Cost savings / TiO₂ replacement: 
Ropaque Opaque Polymer allows formulators to reduce TiO₂ content (which is expensive) while maintaining equivalent hiding performance.

*Low binder demand: 
Because the particles are non-porous and have uniform, spherical shape, their binder demand (how much binder resin they “need” to wet and bind) is lower than many fine inorganic extenders.
This helps maintain film integrity at higher pigment volume concentrations (PVC).

*Compatibility in formulations: 
Good performance in waterborne systems; improved tint retention, washability, color stability in exterior paints.

*Reduced abrasion / dusting: 
In interior paints, the lower count of loose particles (versus some extenders) can lead to better film finish and less abrasion or dust.

 
LIMITATIONS / CHALLENGES of ROPAQUE OPAQUE POLYMER:
*Vulnerability to certain solvents / surfactants: 
Some solvents (especially aromatic solvents) or plasticizers can soften Ropaque Opaque Polymer shell and cause collapse of hollow spheres (thus reducing hiding efficiency) during film formation.

*Need for structural integrity: 
The shell must remain intact during drying and film formation to maintain the void; damage can reduce performance.

*Formulation constraints: 
Because of Ropaque Opaque Polymer's nature, integration into existing paint formulations often requires rebalancing extenders, binders, dispersants, coalescents, and thickeners.

REMARKS, SUMMARY & PRACTICAL NOTES of ROPAQUE OPAQUE POLYMER:
Because Ropaque Opaque Polymer is a functional pigment / polymeric dispersion, you won’t find it in chemical registries as a pure compound with a unique CAS and EC number.
Manufacturers treat Ropaque Opaque Polymer as a mixture / dispersion with its SDS classification as non-hazardous.

The key functional principle is the hollow-sphere structure: the internal void (after drying) of air inside a polymer shell creates a refractive index contrast (air vs polymer), which scatters light to contribute to opacity / hiding in coatings.
The effective use of Ropaque Opaque Polymer in paint formulations requires careful matching with extenders, binders, coalescents, dispersants, and ensuring that harsh solvents or plasticizers do not collapse the spheres.

Safety profile is relatively benign for typical use in coatings (classified non-hazardous in SDS), but dried films / residues can burn; also, care in production / handling to avoid spill, dust, mist exposure, and ensure compatibility.

OTHER BEHAVIOR / STRUCTURAL FEATURES of ROPAQUE OPAQUE POLYMER:
Ropaque Opaque Polymer particles are hollow spheres: initially filled with water in core; upon drying, water diffuses out and the interior becomes air, creating a refractive index contrast (air void inside polymer shell) that scatters light to contribute to opacity (hiding).
The shell polymer is engineered to have a sufficiently high glass transition (Tg) to maintain structural integrity so that the hollow spheres do not collapse under film formation.
The controlled void fraction and narrow particle size distribution are crucial to light scattering efficiency.

BENEFITS AND CHARACTERISTICS of ROPAQUE OPAQUE POLYMER:
*High Opacity: 
Ropaque Opaque Polymer provides excellent hiding power similar to TiO₂ by creating a refractive index difference due to its hollow core.

*Cost Efficiency: 
Ropaque Opaque Polymer reduces TiO₂ usage, lowering formulation cost while maintaining performance.

*Low Density: 
Ropaque Opaque Polymer contributes to lighter-weight coatings.

*Waterborne and Low-VOC: 
Environmentally friendly and compliant with VOC regulations.

*Film Formation: 
Ropaque Opaque Polymer forms continuous films upon drying, maintaining coating integrity.

*Compatibility: 
Easily blended with acrylic, styrene-acrylic, and vinyl-acrylic systems.

*Improved Brightness: 
Ropaque Opaque Polymer enhances whiteness and brightness in coatings and paper applications.

*Durability: 
Ropaque Opaque Polymer provides resistance to yellowing and maintains opacity over time.

PHYSICAL and CHEMICAL PROPERTIES of ROPAQUE OPAQUE POLYMER:
Chemical Type: Synthetic polymer emulsion (acrylic copolymer with hollow-core morphology)
Chemical Nature: Waterborne synthetic latex polymer with encapsulated air voids
Form: Milky white liquid dispersion
Solids Content: Typically 25–40% (depending on grade)
pH: 7.5–8.5
Density: ~1.05 g/cm³
Boiling Point: Approx. 100°C (due to water base)
Flash Point: Not applicable (aqueous dispersion)

AS Number: Mixture (proprietary formulation – individual polymeric components do not have a unique CAS number)
EC Number: Not assigned (mixture)
Appearance: Milky white liquid
Main component: Hollow acrylic copolymer (microspheres 0.3–1.0 µm)
Water content: 60–70%
Solids (polymer) content: 25–40%
pH: 7.5–8.5

Density: ~1.05 g/cm³
Product name / trade name: ROPAQUE™ Opaque Polymer (often in variants like ROPAQUE™ Ultra, ROPAQUE™ Ultra-E, ROPAQUE™ OP-96, ROPAQUE™ OP-62, etc.)
It is not a single small molecule but a polymeric, hollow-sphere polymeric pigment / opacifier (a synthetic polymer dispersion designed to create light scattering in coatings)
Chemical family / composition: Styrene-acrylic copolymer (emulsion polymer) with internal hollow spheres (voids) that are initially filled with water and later convert to air once dried, creating refractive index contrast for scattering light

Styrene/acrylic copolymer (non-hazardous) (~29–31 %)
Water (~69–71 %)
Aqua ammonia (~0.1 %) (for neutralization)
Residual monomers (<0.05 %)
Solids content (wet, by weight): ~30.0 % (for ROPAQUE Ultra)
Volume solids: ~52.1 % (for ROPAQUE Ultra)
pH: ~8.0 – 8.7 (for ROPAQUE Ultra)

Density (wet): ~8.56 lb/gal (≈1.028 g/cm³) (wet)
Density (dry): ~4.93 lb/gal (≈0.591 g/cm³) (dry)
Bulking value (gal / lb): Wet: ~0.117, Dry: ~0.203
Viscosity: < 500 cP (shear of 60 s⁻¹, spindle #2)
Average particle size: ~0.40 µm (for Ultra)
Performance metric: light scattering / hiding efficiency: Very high (designed to provide efficient dry hiding in coatings, enabling partial replacement of TiO₂)
Form: Non-film forming synthetic pigment / polymer dispersion (i.e. the polymer does not itself form a continuous film)

Chemical Type: Acrylic copolymer dispersion (hollow-sphere polymer)
Molecular Formula: Variable (copolymer; not a single formula)
Average Molecular Weight: ~50,000–500,000 g/mol
Main Monomers: Methyl methacrylate, butyl acrylate, methacrylic acid
Form: Aqueous polymer emulsion (milky white)
CAS Number: Mixture (proprietary – no single CAS)
EC Number: Not assigned (polymer blend)

FIRST AID MEASURES of ROPAQUE OPAQUE POLYMER:
-Description of first-aid measures
*General advice:
Show this material safety data sheet to the doctor in attendance.
*If inhaled:
After inhalation: 
Fresh air.
*In case of skin contact: 
Take off immediately all contaminated clothing. 
Rinse skin with
water/ shower.
*In case of eye contact:
After eye contact: 
Rinse out with plenty of water. 
Call in ophthalmologist. 
Remove contact lenses.
*If swallowed:
After swallowing: 
Immediately make victim drink water (two glasses at most). 
Consult a physician.
-Indication of any immediate medical attention and special treatment needed.
No data available

ACCIDENTAL RELEASE MEASURES of ROPAQUE OPAQUE POLYMER:
-Environmental precautions:
Do not let product enter drains.
-Methods and materials for containment and cleaning up:
Cover drains. 
Collect, bind, and pump off spills. 
Observe possible material restrictions. 
Take up dry. 
Dispose of properly. 
Clean up affected area.

FIRE FIGHTING MEASURES of ROPAQUE OPAQUE POLYMER:
-Extinguishing media:
*Suitable extinguishing media:
Carbon dioxide (CO2) 
Foam 
Dry powder
*Unsuitable extinguishing media:
For this substance/mixture no limitations of extinguishing agents are given.
-Further information:
Prevent fire extinguishing water from contaminating surface water or the ground water system.

EXPOSURE CONTROLS/PERSONAL PROTECTION of ROPAQUE OPAQUE POLYMER:
-Control parameters:
--Ingredients with workplace control parameters:
-Exposure controls:
--Personal protective equipment:
*Eye/face protection:
Use equipment for eye protection. 
Safety glasses
*Body Protection:
protective clothing
*Respiratory protection:
Recommended Filter type: Filter A 
-Control of environmental exposure:
Do not let product enter drains.

HANDLING and STORAGE of ROPAQUE OPAQUE POLYMER:
-Conditions for safe storage, including any incompatibilities:
*Storage conditions:
Tightly closed. 
Dry.

STABILITY and REACTIVITY of ROPAQUE OPAQUE POLYMER:
-Chemical stability:
The product is chemically stable under standard ambient conditions (room temperature).
-Possibility of hazardous reactions:
No data available