Sika Technology Ag

Leslie Wolschleger

Karsten Frick

Geng Lin

Dusko Paripovic

Sascha Pasula

Jena Mabilia

Nicolae Bordeanu

Cendrine Ribot

Alina Keller

Engin Cil

Elizabeth Farhat

Artur Marfinati

A one-component thermosetting epoxy resin composition, including a) at least one epoxy resin A having on average more than one epoxide group per molecule; b) at least one latent hardener for epoxy resins; c) at least one physical or chemical blowing agent BA; d) 3-15 wt.-% of at least one carboxyl group containing acrylonitrile/butadiene rubber ABR1 with a Mooney Viscosity of 15-30 MU (Mooney units), based on the total amount of epoxy resin A; and e) 3-15 wt.-% of at least one carboxyl group containing acrylonitrile/butadiene rubber ABR2 with a Mooney Viscosity of 35-50 MU (Mooney units), based on the total amount of epoxy resin A. The ratio of ABR1 to ABR2 is from 0.5-2.0. The epoxy resin adhesive is notable for the improved storage stability.

Ductile one-component thermosetting epoxy composition

A thermally expandable composition, including at least one epoxy-functional polymer, at least one thermoplastic polymer, at least one chemical blowing agent, and at least one activator, wherein the epoxy-functional polymer is present in the composition before expansion with an amount of between 30 and 75 wt.-%, based on the total composition, and the epoxy-functional polymer includes at least 300 mmol epoxy groups per kg polymer, and wherein the chemical blowing agent is able to form at least one reaction product with at least two amino groups upon thermal decomposition, and the chemical blowing agent is in the composition before expansion with an amount of between 5 and 30 wt.-%, based on the total composition.

Approach to heat expandable materials

A thermally expandable composition includes at least one polymer P cross-linkable by peroxide, and at least one acrylate, and at least one peroxide, azodicarbonamide and a zinc compound. The thermally expandable composition leads to low odor formation and low ammonia emission during and after the foaming process. The thermally expandable composition further shows excellent properties in terms of expansion stability.

Thermally expandable composition with reduced odor formation

A thermally expandable composition, including at least one polymer, cross-linkable by peroxide, at least one peroxide, preferably at least one antioxidant, at least one chemical blowing agent, and at least one activator, wherein the activator includes at least one compound selected from formula (I), wherein radicals Rand Rrepresent hydrogen atoms or monovalent alkyl radicals with 1 to 10 carbon atoms which optionally include oxygen atoms; Rand Rrepresent hydrogen atoms or monovalent alkyl radicals with 1 to 10 carbon atoms which optionally include oxygen atoms, nitrogen atoms, and/or aromatic moieties or Rand Rtogether form a divalent alkyl radical with 1 to 10 carbon atoms which optionally includes oxygen atoms, nitrogen atoms or aromatic moieties. The composition shows excellent properties in terms of expansion stability over a wide temperature range, can be expanded at temperatures below 150&#xb0; C. and is suitable for baffle and/or reinforcement elements.

Heat expandable foam for low temperature cure

A composition for an expandable sealant including at least one polymeric material selected from the group consisting of low density polyethylenes (LDPE), linear low density polyethylenes (LLPDE), ethylene vinyl acetate (EVA), ethylene methacrylate (EMA), and ethylene-butyl acrylate (EnBA); and a chemical blowing agent, wherein the composition is substantially free of a cross-linking agent.

Heat expandable foam

Disclosed is a thermally expandable composition, comprising at least one polymer P, cross-linkable by peroxide, and between 1 wt.-% and 2.5 wt.-%, based on the total weight of the composition, of at least one acrylate A, and between 0.2 wt.-% and 2.5 wt.-%, based on the total weight of the composition, of at least one peroxide, and at least one blowing agent, characterised in that the equivalent ratio of said peroxide to said acrylate A is between 0.01 and 0.5, preferably between 0.13 and 0.41, and the weight ratio of said peroxide to said acrylate A is lower than 0.33 and said polymer P comprises or essentially consists of at least two polymers PI and P2, wherein PI exhibits a melt flow index (MFI) of between 100 and 200 g/10 min, and P2 exhibits a melt flow index of between 0.1 and 60 g/10 min, wherein MFI is determined by ASTM D1238. The thermally expandable composition shows excellent properties in terms of expansion stability and minimised buckling and is especially suitable for baffle and/or reinforcement elements, e.g. in automotive manufacturing.

Growing community of inventors

Clarkston, MI, United States of America

Leslie Wolschleger