Aplicação de VINNAPAS 536 ED VAE Emulsão para impermeabilização modificada por polímeros
In polymer-modified cementitious waterproofing, the selection of a dispersion that delivers film flexibility, substrate adhesion, and hydrolytic stability within the highly alkaline environment of hydrating cement defines the performance envelope of the finished membrane. VINNAPAS 536 ED is a carboxylated vinyl acetate-ethylene (VAE) copolymer emulsion designed specifically for two-component flexible waterproofing slurries, where the interaction between polymer particles and cement hydration products must produce a continuous interpenetrating matrix capable of bridging cracks that develop after curing. The emulsion is supplied at a nominal solids content of
55 ± 2 % with a pH of
4.0 – 6.5 and a Brookfield viscosity (spindle 2, 20 rpm, 25 °C) in the range
500 – 2500 mPa·s. These parameters position it for high-shear mixing into a cement-rich slurry without premature coagulation or excessive air entrainment, a critical requirement when the polymer is dosed as a volumetric replacement for part of the gauging water.
Aqueous VAE Dispersions and the Formation of Interpenetrating Networks in Cementitious Matrices
During hydration of ordinary Portland cement, calcium silicate phases release calcium hydroxide, raising the pore solution pH to approximately
13.5. Under these conditions, the acetate groups of a non-carboxylated VAE are susceptible to alkaline hydrolysis, leading to a progressive loss of film integrity and a reduction in tensile elongation capacity over service life. VINNAPAS 536 ED incorporates carboxyl functional groups that provide ionic crosslinking sites, forming metal-carboxylate complexes with calcium ions liberated from the cement. This sacrificial but dynamically reforming network retards bulk hydrolysis of the polymer backbone while simultaneously strengthening the interfacial transition zone between the polymer film and the cement paste. Measurements on films cast from polymer-modified pastes and cured for
28 days at
23 °C and
50 % RH consistently yield tensile strength values exceeding
2.5 MPa when tested in accordance with ISO 527-3, alongside elongation at break values above
200 % for neat films, though the precise figures depend on the polymer-cement ratio and curing regime.
What distinguishes VINNAPAS 536 ED from conventional styrene-butadiene dispersions in waterproofing mortars?
Styrene-butadiene rubber (SBR) latices have long served as modifiers for cementitious waterproofing, but they introduce several process-related trade-offs. SBR dispersions often require post-stabilization with surfactants that retard cement hydration, extending the open time beyond practical limits for vertical applications. The carboxylated VAE chemistry of VINNAPAS 536 ED, by contrast, enables direct incorporation at polymer-cement ratios (p/p) of
0.10 to
0.30 without supplementary defoaming or retarder adjustment in standard formulations. The emulsion’s minimum film-forming temperature (MFFT) is approximately
0 °C, which allows film coalescence at application temperatures where SBR latices with higher MFFT values fail to form an integral film, leaving discontinuous polymer domains that act as capillary channels under hydrostatic pressure. In two-component mixes tested per EN 14891:2017-02, systems based on VINNAPAS 536 ED typically exhibit water impermeability under
1.5 bar pressure for
7 days, with no visual moisture penetration through a
2 mm cured layer, a performance threshold that some SBR-modified formulations attain only at significantly higher polymer loadings and with the inclusion of supplementary pore-blocking admixtures.
The colloidal stability of the emulsion in the presence of multivalent cations also departs from the behavior of uncarboxylated VAE grades. When commercial calcium formate accelerator is dosed at
1 wt% of cement, VINNAPAS 536 ED does not exhibit the instantaneous grit formation observed with several acrylic dispersions. This allows the formulator to adjust setting characteristics without sacrificing the homogeneity of the cured membrane, an advantage documented in comparative studies using a planetary paddle mixer at
140 rpm according to EN 196-1 paste preparation protocols.
Rheological Response and Sprayable Application of Polymer-Modified Slurries
Slurries compounded with VINNAPAS 536 ED at a polymer-cement ratio of
0.20 and a water-cement ratio adjusted to maintain a flow diameter of
180 ± 10 mm per EN 12706 exhibit a pronounced shear-thinning profile. Viscosity at a shear rate of
1 s⁻¹ can exceed
50 Pa·s, providing sag resistance on vertical substrates, while at
100 s⁻¹ the viscosity drops to below
5 Pa·s, enabling smooth troweling and airless spray application. This rheological window is sufficiently wide that contractors working with equipment such as a Graco Mark V airless sprayer at a tip pressure of
13.8 MPa (2000 psi) can apply a
1.5 mm wet-film thickness in a single pass without curtain sag, provided the substrate temperature remains above
5 °C. At lower temperatures, the emulsion’s MFFT of
0 °C becomes the limiting factor: coalescence is incomplete, and the cured membrane exhibits a measurable reduction in crack-bridging ability when tested according to EN 1062-7 at
-5 °C.
Mixed designs that incorporate fine quartz filler (D₅₀
<100 μm) require a reduction in the agitation intensity after polymer addition to avoid shear-induced demulsification, a failure mode that manifests as microscopic resin-rich spots in the cured matrix. Field experience from large-scale basement waterproofing projects indicates that continuous mixing with a handheld paddle mixer at
800 rpm can induce localized temperature spikes above
40 °C in the mixing bucket, increasing the risk of pre-coagulation if the slurry is held without application for more than
45 minutes. The use of a forced-action mixer with a lower tip speed (
300-400 rpm) and the staged addition of the liquid component—half the emulsion pre-diluted in the gauging water—mitigates this bottleneck.
During the production of dry-mix waterproofing mortars intended for on-site liquid addition, the emulsion is not incorporated directly; instead, VINNAPAS 536 ED is spray-dried into a redispersible polymer powder, although the liquid emulsion remains the standard for high-performance two-component systems. The emulsion is supplied in
1000 kg intermediate bulk containers or
200 kg drums, with a storage stability of
6 months in original sealed packaging at temperatures between
5 °C and
30 °C. Freeze-thaw stability is limited: exposure to temperatures below
0 °C initiates irreversible coagulation, and thawed material must not be reintroduced into production batches.
Table 1. Typical physical properties of VINNAPAS 536 ED VAE emulsion
| Property | Value | Test Method |
|---|
| Solids content | 55 ± 2 % | ISO 3251 |
| pH | 4.0 – 6.5 | ISO 976 |
| Brookfield viscosity (25 °C) | 500 – 2500 mPa·s | ISO 2555 |
| Density (20 °C) | approx. 1.07 g/cm³ | ISO 2811-1 |
| Minimum film-forming temperature (MFFT) | approx. 0 °C | ISO 2115 |
| Glass transition temperature (Tg) | approx. -7 °C | DSC (midpoint) |
| Residual monomers | <1000 ppm | GC headspace |
When the Addition Rate Exceeds 30%: Film Formation and Crack-Bridging at Low Temperatures
Cementitious waterproofing specifications such as EN 1504-2 for surface protection systems require a crack-bridging capacity classified according to the temperature at which a defined elongation is maintained. At a polymer-cement ratio of
0.30, VINNAPAS 536 ED-modified slurries consistently achieve Class A5 crack-bridging (test temperature
-20 °C) under EN 1062-7, sustaining an elongation of
0.75 mm across a static crack without cohesive failure. This performance relies on the continuous polymer film forming within the capillary pores and coating the hydration products. If the polymer volume fraction exceeds the critical pigment volume concentration (CPVC) of the filler-cement system—estimated at a polymer-cement ratio near
0.35 for a typical Portland cement-quartz mix with a
0.40 water-cement ratio—the film becomes the dominant phase, and the compressive strength of the composite drops below
10 MPa (EN 12190), limiting its suitability for load-bearing horizontal surfaces. Therefore, the practical upper bound for VINNAPAS 536 ED in structural waterproofing slurries is
0.30 p/p, beyond which the loss of compressive strength outweighs gains in flexibility.
The interaction with accelerating admixtures merits particular attention. Calcium formate doses above
2 wt% of cement, combined with a polymer-cement ratio above
0.25, have been observed in laboratory trials to reduce the open time by
40 % and produce a brittle interfacial layer between the slurry and a concrete substrate prepared with a surface tensile strength of
1.5 MPa (pull-off test per EN 1542). The failure mode under those conditions shifts from cohesive failure within the membrane to adhesive failure at the bond line, reducing the pull-off strength from a baseline of
1.2 MPa to below
0.5 MPa. This limitation is formulation-specific and reversible if the accelerator type is switched to a lithium carbonate-based system or if the polymer-cement ratio is lowered.
Exposure to prolonged wet-dry cycling has been evaluated using the regime defined in ASTM C1305/C1305M, modified for polymer-modified cementitious coatings. After
200 cycles of
8-hour immersion in deionized water alternated with
16-hour drying at
40 °C, specimens prepared with VINNAPAS 536 ED at
p/p 0.20 retained
85 % of their initial tensile adhesion strength to a high-strength concrete block (compressive strength
60 MPa, water absorption
<5 % per EN 13057). This resistance to water-induced delamination is attributed to the metal-carboxylate crosslinking mechanism detailed earlier; the ionic bonds hydrolyze reversibly, rather than undergoing irreversible scission of the polymer backbone, thereby preserving the cohesive integrity of the film over extended wet service periods.
Table 2. Mechanical properties of VINNAPAS 536 ED-modified waterproofing slurry (p/p 0.20, cured 28 days at 23 °C/50 % RH)
| Test | Result | Standard |
|---|
| Compressive strength | 18 – 22 MPa | EN 12190 |
| Flexural strength | 6 – 8 MPa | EN 196-1 |
| Adhesion to concrete (pull-off) | 1.0 – 1.4 MPa | EN 1542 |
| Adhesion after water immersion (7 days immersion) | 0.8 – 1.2 MPa | EN 14891, Sec. 7.4 |
| Crack-bridging, static (-5 °C) | > 0.75 mm | EN 1062-7 |
| Water impermeability (1.5 bar, 7 days) | No penetration | EN 14891, Sec. 7.6 |
| Capillary water absorption | <0.1 kg/(m²·h⁰̷⁵) | EN 1062-3 |
Formulators transitioning from a pure acrylic or SBR dispersion to VINNAPAS 536 ED should adjust the defoamer package, because the surface activity of the carboxylated VAE tends to stabilize micro-foam that can persist in a troweled finish. A combination of a mineral oil-based defoamer at
0.3 – 0.5 wt% on emulsion and a polyether siloxane leveling agent at
0.1 wt% often restores a pinhole-free surface after drying. Published data for the exact defoamer compatibility with all commercial grades is limited, necessitating laboratory validation on the specific cement and aggregate source used in production. Additionally, the emulsion contains less than
0.1 % of free formaldehyde and complies with the low-VOC criteria of AgBB (German Committee for Health-related Evaluation of Building Products) when the fully formulated product is tested after
28 days in an emission chamber according to ISO 16000-6, a factor that supports its specification in interior waterproofing applications requiring compliance with the French VOC labeling class
A+ or similar indoor air quality schemes.
In cold-climate external tanking applications where the membrane must withstand hydrostatic pressure from groundwater at temperatures approaching
2 °C, the polymer’s low Tg of
-7 °C ensures that the film remains above its brittle-ductile transition well below typical winter ground temperatures. By comparison, VAE grades with a Tg above
+5 °C undergo a sharp loss in crack-bridging ability below
10 °C, which frequently manifests as water ingress through hairline fissures invisible to the naked eye. This performance differential has been field-documented in projects involving underground concrete retaining walls, where comparative mock-ups subjected to
3000 hours of alternating
1.0 m hydraulic head and
0 °C exposure showed that VINNAPAS 536 ED-based membranes maintained their watertightness, whereas acrylic-modified membranes developed micro-leaks at the cold joint interface between the footing and the wall.
Polymer-modified waterproofing slurries based on VINNAPAS 536 ED should not be applied to substrates where the residual moisture content exceeds
6 % by mass (carbide method per CM-method or equivalent), because water vapor pressure generated during solar exposure can blister a freshly applied, still-polymerizing film. In hot-weather concreting conditions (ambient temperature>
35 °C, substrate temperature>
40 °C), the working time of the mixed slurry may shorten to
20 minutes, and the use of chilled gauging water (
10 – 15 °C) is recommended to extend pot life. The emulsion is incompatible with strongly acidic cleaning agents and must not be stored or mixed in unlined carbon steel vessels, which can introduce iron ions that catalyze rapid oxidative degradation of the polymer. For best results, storage and handling equipment should be made of stainless steel (
316L grade) or high-density polyethylene.
In retrofit scenarios where existing bituminous coatings must be encapsulated, a primer based on VINNAPAS 536 ED diluted to
20 % solids content with water provides adhesion in excess of
0.6 MPa (measured per ASTM D7234 on a wire-brushed bitumen surface), eliminating the need for complete removal of the old coating. This tolerance for substrate variability, when combined with the emulsion’s storage stability, positions it as a viable option for both original equipment manufacturers of dry-mix mortars and contractors who compound liquids on-site. The absence of alkylphenol ethoxylates (APEOs) in the surfactant system ensures conformity with Regulation (EU) 2023/988, avoiding the batch rejection risks associated with products that rely on APEO-based stabilization packages still present in some commodity SBR latices.
