Rheological, Mechanical and Adhesion Properties of Two Component Adhesive based on Modified Silyl-Terminated Polyether Polymer and Epoxy Resin

Today an increasing interest in two component adhesive products can be sensed in the market. The driving force requesting more specific adhesive materials is automotive industry for bonding of light-weight structures or challenging designs. These requirements from industry make to seek for new raw material types to formulate adhesive systems with higher strength, broad superior adhesion spectrum and other demanding properties. The combination of epoxy resin with modified silyl-terminated polyether polymer (MS Polymer) is supposed to deliver a two component adhesive that shows superior strength compared to pure MS Polymer based adhesives, while combining all the other positive features from both polymer resin types. In two component adhesive formulation MS Polymer and epoxy hardener are main ingredients of one component and epoxy, MS Polymer catalyst and water are main ingredients of other component. Depending on the amount of methoxysilyl groups various MS Polymer types, namely, di-functional MS Polymers (DMS) and tri-functional MS Polymers (TMS), were used. Rheological characteristics were measured by using Bohlin CVO 100 rheometer. Instrument was equipped with 20 mm diameter spindle in plate-plate geometry with gap size 1000 m. Tests at 23 oC were performed in oscillatory shear mode at frequency 1.5 Hz and strain 0.15. Dynamic storage G’ and loss moduli G” were recorded as functions of the reaction time. Adhesive and tensile stress-strain characteristics were determined by using Zwick/Roell Z010 universal testing machine. Tensile tests were made according to DIN 53504. Lap shear tests were made according to EN 1465. Samples were tested after 1, 7, 14, 21 and 28 days of curing

Rheological, Mechanical and Adhesion Properties of Two Component Adhesive based on Modified Silyl Terminated Polyether Polymer and Epoxy Resin

4 types of two component adhesives based on modified silyl-terminated polyether polymer (MS Polymer) and epoxy resin are formulated. Rheological and mechanical properties as well as weathering resistance of the developed adhesives are investigated. It is shown that curing times vary in a wide range depending on the type of MS Polymer. It is also demonstrated that kinetics of cross-linked network formation of the investigated adhesives, depending on the type of MS Polymer, considerably affects mechanical characteristics of the system: Shore A hardness, tensile strength and tensile elongation. Although under the influence of UV weathering mechanical properties of the investigated systems are decreased, the remaining tensile elongation values are not less than 30%. In parallel it is revealed that adhesive formulations, developed in the framework of this research, are most suitable for bonding with stainless steel, partially suitable for bonding with aluminium and less suitable for bonding with polyvinyl chloride

Modified Silyl-Terminated Polyether Polymer Blends with Bisphenol A Diglycidyl Ether Epoxy for Adhesive Applications

Modified silyl-terminated polyether polymer (MS Polymer) was blended with bisphenol A diglycidyl ether (DGEBPA) epoxy at MS Polymer/epoxy ratio from 30/70 to 70/30. MS Polymer/epoxy systems were examined for two-component adhesive formulation with additional fillers. Applicability of the MS Polymer/epoxy system at the ratio of the components 60/40 is demonstrated for the development of adhesive formulation. Rheological analysis of the components A and B shows suitable viscosity values for development of two- component adhesives formulation. Curing dynamics as well as tensile stress-strain properties and Shore A hardness of the chosen adhesive formulation are reasonable for the development of MS Polymer/epoxy type adhesive

Modified Silyl-Terminated Polyether Polymer Blends with Bisphenol a Diglycidyl Ether Epoxy for Adhesive Applications

Epoxy resins have been used successfully as adhesives for many years. Despite many advantages of epoxy resins like high strength, chemical and heat resistance, in many applications they lack flexibility. During service under dynamic stress and variable environment this may lead to cracking and even failure of the adhesive joint. To improve epoxy resin adhesive performance they can be modified with other polymers. In this work modified silyl-terminated polyether polymer (MS Polymer) was used as elastic matrix material in various mixing ratio with epoxy resin. In the MS Polymer/epoxy blend A component consists from MS Polymer, amine catalyst, aminosilane and additional fillers. B component is based on bisphenol A diglycidyl ether (DGEBPA) epoxy resin with tin catalyst, water and fillers. When epoxy resin is mixed together with MS Polymer at the right ratio they form heterogenic matrix/domain structure which consists of the epoxy domains functioning as hard segments in elastic MS Polymer matrix [1]. When A and B components are mixed together, curing happens by epoxy reacting with amine catalyst, at the same time MS Polymer reacting with water. Aminosilane links MS Polymer with epoxy. Tensile stress-strain characteristics according to DIN 53504 were determined by using Zwick/Roell Z010 universal testing machine. Fracture surfaces of brittle-broken test specimens were observed by using Mira/LMU field emission scanning electron microscope (TESCAN a.s.)