Product 408

　　October 1998

　　NOT FOR PRODUCT SPECIFICATIONS.

　　THE TECHNICAL DATA CONTAINED HEREIN ARE INTENDED AS REFERENCE ONLY.

　　PLEASE CONTACT LOCTITE CORPORATION QUALITY DEPARTMENT FOR ASSISTANCE AND RECOMMENDATIONS ON SPECIFICATIONS FOR THIS PRODUCT.

　　ROCKY HILL, CT FAX: +1 (203)-571-5473 DUBLIN, IRELAND FAX: +353-(1)-451 - 9494

　　PRODUCT DESCRIPTION

　　LOCTITE. Product 408 is a very low viscosity cyanoacrylate

　　adhesive with low odour and non-blooming characteristics.

　　TYPICAL APPLICATIONS

　　Bonding applications where vapour control is difficult.

　　PROPERTIES OF UNCURED MATERIAL

　　Typical

　　Value Range

　　Chemical Type Alkoxy-ethyl

　　cyanoacrylate

　　Appearance Water white to straw

　　coloured liquid

　　Specific Gravity @ 25°C 1.1

　　Viscosity @ 25°C, mPa.s (cP)

　　Brookfield LVF

　　Spindle #1 @ 60 rpm 7 4 to 10

　　Flash Point (TCC), °C >82

　　TYPICAL CURING PERFORMANCE

　　Under normal conditions, the surface moisture initiates the

　　hardening process. Although full functional strength is

　　developed in a relatively short time, curing continues for at

　　least 24 hours before full chemical/solvent resistance is

　　developed.

　　Cure speed vs. substrate

　　The rate of cure will depend on substrate used. The table

　　below shows the fixture time achieved on different materials at

　　22°C , 50% relative humidity. This is defined as the time to

　　develop a shear strength of 0.1 N/mm2 (14.5 psi) tested on

　　specimens according to ASTM D1002.

　　Substrate Fixture Time, seconds

　　Steel (degreased) 30 to 70

　　Aluminium 5 to 20

　　Neoprene <5

　　Nitrile rubber <5

　　ABS 20 to 60

　　PVC 20 to 50

　　Polycarbonate 20 to 60

　　Phenolic materials 30 to 60

　　Cure speed vs. bond gap

　　The rate of cure will depend on the bondline gap. High cure

　　speed is favoured by thin bond lines. Increasing the bond gap

　　will slow down the rate of cure.

　　Cure speed vs. activator

　　Where cure speed is unacceptably long due to large gaps,

　　applying activator to the surface will improve cure speed.

　　However, this can reduce the ultimate strength of the bond,

　　therefore testing is recommended to confirm effect.

　　TYPICAL PROPERTIES OF CURED MATERIAL

　　Physical Properties

　　Coefficient of thermal expansion, ASTM D696, K-1 80x10-6

　　Coefficient of thermal conductivity, ASTM C177, W.m-1 K-1 0.1

　　Glass Transition temperature, ASTM E228, °C

　　Electrical Properties

　　Dielectric constant & loss, 25°C, ASTM D150:

　　Constant Loss

　　measured at 50Hz: 2.3 <0.02

　　1kHz: 2.3 <0.02