SikaBiresin CR
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PRODUCT DATA SHEET
SikaBiresin CR128
Version 01.01 (08 – 2023), en_US
PRODUCT DATA SHEET
SikaBiresin CR128 (Formerly EL-336)
Unfilled Epoxy Laminating System for High Temperature Applications
TYPICAL PHYSICAL PROPERTIES (FOR FURTHER VALUES SEE SAFETY DATA SHEET)
DESCRIPTION
SikaBiresin CR128 is an unfilled, non- staining,
epoxy laminating system that provides room
temperature hardening (B Stage) and is
designed for high temperature laminating and
tooling applications. SikaBiresin CR128 has
excellent handling properties and fabric wet-
out to produce a void free tool with high
dimensional stability. SikaBiresin CR128 is
availble with a choice of two hardener options
with different pot lifes for process flexibility.
Tools made with SikaBiresin CR128 can be used
at continuous temperatures of 230 F (110 C)
and up to a 250 F (121 C) intermittent use
maximums. While SikaBiresin CR128 will gel at
room temperature, it must be post-cured to
achieve ultimate strength.
PRODUCT BENEFITS
– For applications up to 250 F (121 C)
– High mechanical properties
– Two hardener choices (fast and slow)
– Excellent cloth wet-out
– Excellent dimensional stability
– Good handling properties
AREAS OF APPLICATION
Typical applications include vacuum form
molds, prototype injection molds, high
temperature bonding fixtures, spray metal
molds, compression molds, high temperature
laminating molds and parts for intermediate
to high temperature applications
SikaBiresin CR128 can be used with Sika s h igh
temperature surface coats SP-707, ES-221, or
ES-224.
Properties
SikaBiresin CR128 (A)
Resin
SikaBiresin CH128-2 (B)
Hardener
SikaBiresin CH128-4 (B)
Hardener
Composition Epoxy Amine Amine
Mix ratio by weight 100 22 27
Aspect Clear liquid Clear liquid Clear liquid
Color (mixed) n/a Clear Clear amber
Viscosity Brookfield (mixed) n/a 2,000 – 3,000 cps 1,400 cps 1,600
Density at 77 F (25 C) (mixed) n/a 9.51 lbs./gal n/a
Pot life (228g) at 77 F (25 C) n/a 35 – 50 Minutes 120 140 Minutes
SikaBiresin
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Sika Corporation
30800 Stephenson Highway
Madison Heights, MI 48071
U.S.A.
Telephone: +1 248- 577-0020
Email: tsmh@us.sika.com
www.sikaindustry.com
TYPICAL MECHANICAL AND THERMAL PROPERTIES (NEAT FORM)
PROCESSING
Preliminary self-support cure schedule: Cure
for 24 hours at 77 F (25 C) + 4 hours at 125 F
(51.6 C) – 140 F (60 C). You may attach
support structure and demold tool after this
schedule is completed before additional cure
is given.
Alternative post-cure options can be used, if
needed, in processing. Contact Sika Corporation s
Industry Technical Services Department at
tsmh@us.sika.com for additional information and
advice.
Heating and cooling rates durng post-cure:
Always allow tools made with Sika high
temperature systems to gel at room
temperature before subjecting them to post
cure (24 hours is usually sufficient). This will
prevent excessive exotherm and shrink stress
from occurring. When oven curing laminated
molds, always place mold in a room
temperature oven and increase temperature
at a rate of no more than 50 F (30 C) per hour.
When heat cure is completed, turn off oven
and allow molds to remain in the oven. Never
remove mold from oven until mold
temperature has been lowered to less than
100 F (38 C).
Normal health and safety precautions should be
observed when handling these products:
Ensure adequate ventilation
Wear gloves, glasses, and protective clothes
For further information, please consult the Safety
Data Sheets
STORAGE CONDITIONS
Shelf life of resin and hardeners is 24 months
when stored in original, unopened containers
between 65-77 F (15 – 25 C). Keep containers
tightly closed.
PACKAGING INFORMATION
Packaging information is available upon
request. Please contact your local Sika sales
representative.
FURTHER INFORMATION
Advice on specific applications will be given on
request. To contact Sika Corporation s Industry
Technical Services Department, send an email to
tsmh@us.sika.com. Copies of Safety Data
Sheets and Product Data Sheets are available
upon request.
BASIS OF PRODUCT DATA
All technical data stated in this document are
based on laboratory tests. Actual measured data
may vary due to circumstances beyond our
control.
ENVIRONMENTAL, HEALTH AND SAFETY
For further information and advice regarding
transportation, handling, storage and disposal of
chemical products, user should refer to the
actual Safety Data Sheets containing physical,
environmental, toxicological and other safety
related data. User must read the current
actual Safety Data Sheets before using any
products. In case of an emergency, call
CHEMTREC at 1-800-424-9300, International
703-527-3887.
LEGAL DISCLAIMER
Prior to each use of any product of Sika Corporation,
its subsidiaries or affiliates ( SIKA ), the user must
always read and follow the warnings and
instructions on the product s most current product
label, Product Data Sheet and Safety Data Sheet
which are available at usa.sika.com or by contacting
SIKA s Technical Service Department via email at
tsmh@us.sika.com. Nothing contained in any SIKA
literature or materials relieves the user of the
obligation to read and follow the warnings and
instructions for each SIKA product as set forth in the
current product label, Product Data Sheet and
Safety Data Sheet prior to use of the SIKA product.
SIKA warrants this product for one year from date
of installation to be free from manufacturing
defects and to meet the technical properties on the
current Product Data Sheet if used as directed
within the product s shelf life. User determines
suitability of product for intended use and assumes
all risks. User s and/or buyer s sole remedy shall be
limited to the purchase price or replacement of this
product exclusive of any labor costs. NO OTHER
WARRANTIES EXPRESS OR IMPLIED SHALL APPLY
INCLUDING ANY WARRANTY OF
MERCHANTABILITY OR FITNESS FOR A
PARTICULAR PURPOSE. SIKA SHALL NOT BE LIABLE
UNDER ANY LEGAL THEORY FOR SPECIAL OR
CONSEQUENTIAL DAMAGES. SIKA SHALL NOT BE
RESPONSIBLE FOR THE USE OF THIS PRODUCT IN A
MANNER TO INFRINGE ON ANY PATENT OR ANY
OTHER INTELLECTUAL PROPERTY RIGHTS HELD BY
OTHERS. Sale of SIKA products are subject to the
Terms and Conditions of Sale which are available at
https://usa.sika.com/en/group/SikaCorp/termsand
conditions.html or by calling +1 800-933-7452.
Properties, Test Method
Mixed with SikaBiresin CR128 (A) Resin
SikaBiresin CH128-2 (B)
Hardener
SikaBiresin CH128-4 (B)
Hardener
Shore D hardness, ASTM D2240 88 88
Compressive strength, ASTM D695 13,390 psi (92 MPa) 15,910 psi (110 MPa)
Tensile elongation, ASTM D638 3.0% n/a
Heat Distortion Temperature (HDT) (66 psi)
(264 psi)
n/a
n/a
278 F (137 C)
263 F (128 C)
Coefficient of Thermal Expansion (CTE) – TMA 30 ppm/ F (54 ppm/ C) n/a
Notched Impact strength, ASTM D256 7.0 in-lbf/in n/a
Cured 24 hours at 77 F (25 C) + 2 hours at 150 F (66 C) + 2 hours at 200 F (93 C) + 2 hours at 250 F (121 C) + 3 hours at 300 F
(149 C).