Overview:

At the request of medical customers, Beijing Lianhe launches FibKey 8218-Med, a biocompatible epoxy adhesive. It has passed authoritative testing: the test sample showed no potential cytotoxicity in the MTT cytotoxicity test.

Overview:

FibKey 8218-Med is a two-part high-temperature epoxy that is low-odor, low-allergen and non-toxic, meeting biocompatibility requirements. Typical use: producing medical fiber-optic devices.
FibKey 8218-Med handles well with over 3 h pot life, excellent flow and strong capillary action; after dispensing it self-distributes evenly in tiny holes such as ceramic ferrules, and bubbles are easy to remove. Color slowly changes from light yellow to amber on cure, so full cure is judged by color rather than time. Glossy cured surface with excellent light transmission; grinds off quickly with standard polishing film after fiber connector production.

This high-temperature epoxy with strong adhesion is also suitable for assembling and producing other medical devices. After cure, FibKey 8218-Med resists chemicals, water and moisture excellently.

Properties:

1. No fogging or oily surface after cure.

2. Low viscosity, good flow, easy potting.

3. Excellent light transmission after cure.

4. Good electrical insulation under high humidity.

5. About 3 h pot life after mixing.

6. Good resistance to chemicals and solvents after cure.

Specifications:

Item	Parameter
Appearance	ALiquid； BLiquid
Color	Clear, colorless Clear, colorless
Viscosity 25 ℃, cps (Brookfield, S14, 10rpm)	2500~4600
Specific Gravity 20/20℃	1.23

Curing Conditions:

Mix Ratio A:B (by weight): 10:1

Working Time at 25℃, 3 h

Full Cure Time @150°C: 60 min

Cured Properties:

Item	Parameter
Number of Components	2
Refractive Index @ 589.3nm	1.573
Cured Specific Gravity	1.23
Shore Hardness	80
Viscosity, Part A, 25℃, Cps, S14 100rpm	2500~4600
Viscosity, Part B, 25℃, Cps, S21 50rpm	300~500
Viscosity (mixed) 25℃, Cps, S14 100rpm	2000-3000
Glass Transition Temp (Tg)	109℃
Decomposition Temperature	351℃
Adhesive Strength Al/Al, kgf/cm2	267
CTE:
< Tg	56 μm/m/℃
> Tg	230 μm/m/℃
Operating Temperature Range	-55~200℃
Water Absorption:
25 ℃, 24 h, %	0.61
80 ℃, 24 h, %	4.89
97 ℃, 1.5 h, %	1.58
Transmittance:
@ 550nm, %	> 50
@ 700-1,000nm, %	> 98
@ 1,100-1,600nm, %	> 95
Weight Loss:
@ 250° C, %	1.09
@ 300° C, %	2.35
@ 350° C, %	4.95
Thermal Conductivity, W/mK	0.3
Dielectric Constant, 1KHz	3.2
Pot Life	3 h

Storage

Storage: 1 year at 5-25°C. Close the lid after each use and store at room temperature. Before mixing, no refrigeration needed; do not store in a refrigerator. Below 5°C the adhesive may crystallize; if crystals form, dissolve them before use. Crystallization is not a quality issue and does not affect continued use if handled properly. Contact us for detailed methods to dissolve crystals.

Packaging

Currently FibKey 8218-Med is supplied in the following packaging:

FibKey 8218-Med matches Med-353ND in performance and applications.