One-Step Resins
One-step resins are often referred to as resoles. These resins will cure with the
application of heat and have good compatibility with NBR. These resins are used
primarily in the formulation of solvent-based adhesives. Akrochem’s one-step resin
for this application and others like it is as follows:
BRJ-473 (P-102)
BRJ-473 is a thermosetting phenolic resin used primarily in the formulation of NBR
adhesives. BRJ-473 is supplied as a solution in methyl-ethyl-ketone (MEK) and can
be easily blended directly into solutions of rubber. Adhesives based on combinations
of BRJ-473 with NBR have excellent oil and vinyl plasticizer resistance, high bond
strengths and stable viscosity.
Heat Reactive Resins
The most signifcant use of heat reactive phenolic resins is in modifying the properties of
polychloroprene cements. The addition of phenolic resin, magnesium oxide, zinc oxide
and a small amount of water greatly improves the heat resistance and chemical bonding
of a polychloroprene cement.
A frequent complaint in making polychloroprene adhesives is inadequate open time.
Changing resins, from one with a short open time to one with a longer open time,
is the most common means of dealing with this issue. However, a gain in open time
usually results in a sacrifce in heat resistance. Akrochem’s heat reactive resins for this
application and others like it are as follows:
SP-134 (P-28)
SP-134 is a modifed alkyphenol-formaldehyde resin used in making polychloroprene
contact cements that require long open times. It can also be used in formulating
adhesives with NBR, SBR, Natural and reclaimed rubbers. SP-134 is completely
compatible with NBR and CR. It has a compatibility limit of approximately 25 parts by
weight in combination with 100 parts by weight of SBR, Natural and reclaimed rubbers.
SP-103 (P-109)
SP-103 is a modifed alkylphenol-formaldehyde resin used in making polychloroprene
contact cements. The outstanding features of this resin are its light color and ability
to extend open time without affecting other properties of the fnished adhesive. It can
also be used in formulating adhesives with NBR, SBR, Natural and reclaimed rubbers.
SP-103 is completely compatible with NBR and CR. It has a compatibility limit of
approximately 25 parts by weight in combination with 100 parts by weight of SBR,
Natural and reclaimed rubbers.
One-Step Resins
Product
Melting Point
Capillary Method (°F)
Physical Form
Hexa Content (%)
Specifc Gravity
BRJ-473 (P-102)
N/A
Liquid
None
1.10