PERMABOND UV625
Harmonization Code : 3907.30.00.40 | Epoxy Mold Compounds containing by weight more than 70 % silicon dioxide
Main features
- Non-Drip Vertical Bonding
- Larger-Gap UV Application
- Flexible Impact-Resistant Cure
Product Description
Permabond UV625 is a single-part, non-drip methacrylate gel for UV-curing glass-to-metal bonds and seals. Its gel-like, shear-dependent viscosity supports vertical surfaces and larger gaps while limiting flow before cure. Typical fixture time ranges from 5 seconds with a 4 mW/cm^2 battery lamp to 1 second with a 30 W/cm^2 light guide across a 365 to 400 nm cure range. The cured adhesive is tough and flexible, with typical tensile strength of 16 N/mm^2, elongation above 60%, and steel-to-glass tensile strength of 6 to 10 N/mm^2.
Key features
- Non-Drip Vertical Application: Gel-like rheology limits flow on vertical bonding and sealing surfaces.
- Larger-Gap UV Bonding: Good depth of cure supports larger-gap UV applications.
- Flexible Impact-Resistant Cure: Cures to a tough, flexible bond with good impact resistance.
Applications
Applications include glass-to-metal bonding and sealing, vertical assemblies, and UV-curable joints with larger gaps.
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Appearance
Colorless gel
Appearance at room temperature.
Refractive index
>1.490
The refractive index determines how much the path of light is bent, or refracted, when entering a material. It is calculated by taking into account the velocity of light in vacuum compared to the velocity of light in the material.
The refractive index calculation can be affected by the wavelength of light and the temperature of the material. Even though it is usually reported on standard wavelengths it is advised to check the TDS for the precise test parameters.
Specific Gravity
1.0
Specific gravity (SG) is the ratio of the density of a substance to the density of a reference substance; equivalently, it is the ratio of the mass of a substance to the mass of a reference substance for the same given volume.
For liquids, the reference substance is almost always water (1), while for gases, it is air (1.18) at room temperature. Specific gravity is unitless.
Physical Properties
Viscosity
30,000-55,000 mPa.s
Viscosity is a measurement of a fluid’s resistance to flow.
Viscosity is commonly measured in centiPoise (cP). One cP is defined as
the viscosity of water and all other viscosities are derived from this base. MPa is another common unit with a 1:1 conversion to cP.
A product like honey would have a much higher viscosity -around 10,000 cPs-
compared to water. As a result, honey would flow much slower out of a tipped glass than
water would.
The viscosity of a material can be decreased with an increase in temperature in
order to better suit an application
Mechanical Properties
Elongation
>60 %
Elongation is the process of lengthening something.
It is a percentage that measures the initial, unstressed, length compared to the length of the material right before it breaks.
It is commonly referred to as Ultimate Elongation or Tensile Elongation at break.
Electrical Properties
Dielectric Strength
12 kV/mm
Dielectric strength is measured in kV per mm and is calculated by the Breakdown voltage divided by the thickness of the tested material.
Those two properties go hand in hand and while Breakdown voltage is always thickness dependent, dielectric strength is a general material property.
As an example, the dielectric strength of Polyimide is 236 kV/mm. If we place 1mm of Polyimide between two electrodes, it will act as an insulator until the voltage between the electrodes reaches 236 kV. At this point it will start acting as a good conductor, causing sparks, potential punctures and current flow.
Chemical Properties
Water Absorption
<4 %
Other Properties
Storage Temperature
5 - 25 °C
Additional Information
Technical properties
As-supplied / before-processing properties
Fixture time depends on lamp power, spectral output, distance, and substrate transmission.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Chemical composition | Methacrylate ester | As supplied | |
| Appearance | Colorless gel | As supplied | |
| Viscosity | 30,000 to 55,000 | mPa s | At 25 deg C; 20 rpm |
| Viscosity | 120,000 to 250,000 | mPa s | At 25 deg C; 2.5 rpm |
| Specific gravity | 1.0 | As supplied | |
| Fixture time | 5 | seconds | 4 mW/cm^2 battery lamp |
| Fixture time | 2 | seconds | 100 mW/cm^2 LED lamp |
| Cure wavelength | 365 to 400 | nm | Match lamp output to the photoinitiator |
Technical properties
After-processing / final-state properties
Strength and dielectric values are typical cured results for the stated methods.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Steel-to-glass tensile strength | 6 to 10 | N/mm^2 | ASTM D-2095-69 |
| Tensile strength | 16 | N/mm^2 | ISO 37 |
| Refractive index | >1.490 | Cured adhesive | |
| Elongation | >60 | % | ISO 37 |
| Hardness | 60 to 70 | Shore D | ISO 868 |
| Dielectric strength | 12 | kV/mm | Typical cured value |
| Dielectric constant | 4 | 1 MHz at 25 deg C | |
| Water absorption | <4 | % | ISO 62; 2 hours in boiling water |
