Analysis of paints or varnishes

Definition/objectives:

The characterization of a paint or varnish is necessary for product qualification prior to marketing. It can also be carried out following a product failure (stain, adhesion problem, flaking, color change...) in order to identify its origin.

Performance measurement (standards and equipment testing)

Check that paint or varnish complies with specifications
specifications (pigment type, quality level, etc.),
regulatory standards (REACH, VOCs, lead and heavy metals),
industrial requirements.
Analyze chemical composition
Chemical resistance tests: Resistance to MEK (Methyl Ethyl Keton) after polymerization, Resistance to washability/cleaning: ethanol, isopropanol, KOH-based detergent, agent containing alkaline surfactant (tensiometer), etc., Resistance to contact with milk, butter, ketchup, jam, lemon, mustard, vinegar, tomato sauce, tea, coffee and olive oil.
Analyze coating performance under different stresses (ageing study in climatic chambers (ISO 9227 / ASTM B 117);
Various adhesion tests: bending on cylindrical mandrel (standard 1519) , Cross-cut (standard 2409) , Tensile test (standard 4624) ,Mass drop test (standard 6272) ;
Friction and abrasion resistance (ISO 11998), Hardness measurements, scratch resistance (SO15184, ASTM D 3363), Pencil hardness, impact test, Persoz hardness (standard 1522), Automatic drawing test (standard 1520);
Through-drying time (ISO 9117-1); degree of drying (ISO 9117-5),
Thermal resistance evaluation
TGA analysis (under O2 or N2)
Thermal shock (O2) 700°C-650°C
Characterization of surface coatings
Thickness measurements (optical profilometers and/or dektak)
Roughness measurements (granulo laser)
Nanosizer
Dynamic rheometer
Density determination - Pycnometric method (ISO 2811-1)
L*a*b* and Gloss measurements, Colorimetry (ISO 7724 and ASTM D6290), Gloss (ISO 2813), Masking power (ISO 6504).
Surface energy measurement (wettability ISO 19403).
FTIR analysis (evaluation of cross-linking/polymerization on coated samples).
SEM analysis (top surface morphology and cross-sectional observations)
Evaluation of hydrophobicity/slip and surface energy on coated samples: measurements of water contact angle, slip angle).
ToF Sims: elemental, isotopic or molecular composition at the extreme surface of samples (<1 nm depth) by mass spectrometry
XPS: atomic composition and chemical environment of surface elements of solid materials (5-10 nm deep), including insulators, organics, polymers, powders, metals and glasses.
Aging tests
Climatic chamber (CC) (temperature, humidity, corrosive gases)
QUV test