Adhesive Performance of Acrylic Pressure-Sensitive Adhesives from Different Preparation Processes

Abstract

A series of pressure-sensitive adhesives (PSAs) was prepared using a constant monomeric composition and different preparation processes to investigate the best combination to obtain the best balance between peel resistance, tack, and shear resistance. The monomeric composition was a 1:1 combination of two different water-based acrylic polymers—one with a high shear resistance (A) and the other with a high peel resistance and tack (B). Two different strategies were applied to prepare the adhesives: physical blending of polymers A and B and in situ emulsion polymerization of A + B, either in one or two steps; in this last case, by polymerizing A or B first. To characterize the polymer, the average particle size and viscosity were analyzed. The glass transition temperature (Tg) was determined by differential scanning calorimetry (DSC). The tetrahydrofuran (THF) insoluble polymer fraction was used to calculate the gel content, and the soluble part was used to determine the average sol molecular weight by means of gel permeation chromatography (GPC). The adhesive performance was assessed by measuring tack as well as peel and shear resistance. The mechanical properties were obtained by calculating the shear modulus and determination of maximum stress and the deformation energy. Moreover, an adhesive performance index (API) was designed to determine which samples are closest to the requirements demanded by the self-adhesive label market.

Influence of Methacrylate and Vinyl Monomers on Radical Bulk Photopolymerization Process and Properties of Epoxy-Acrylate Structural Adhesives

“…230 °C), suspension polymerization or polymerization in supercritical carbon dioxide [ 1 ]. EA polymers can be classified as special types of acrylic resins (ARs) that are widely used to produce coatings, adhesives, printing inks, dental materials [ 2 , 3 , 4 , 5 , 6 , 7 ] or in 3D printing [ 8 , 9 ]. The popularity of ARs is evidenced by the value of the global market (16.8 billion in 2020 and is expected to reach 21.9 billion in 2025) [ 10 , 11 ].…”

Moisture-cured solvent free silylated poly(ether-urea) pressure-sensitive adhesives (PSAs) for use as skin adhesives for application in transdermal drug delivery (TDD)

“…5 Most commercial PSAs are polymers which fall in the category of natural and synthetic rubbers, acrylics, polyurethanes and silicones. 6,7 Among these, rubber-based PSAs are used extensively but generally lack the appropriate tack and adhesion which can only be achieved with tackifier resins and fillers. Their poor resistance towards chemical and environmental factors is characteristic.…”

Effect of Residue Acrylic Monomers in Synthesized Solvent-Free Photoreactive Pressure-Sensitive Adhesives on the Main Properties of Transfer Tapes Applied to Joining Wooden Elements

“…Since the introduction of pressure-sensitive acrylic adhesives over half a century ago, they have been successfully applied in many fields of industry. PSAs are used in self-adhesive tapes [2][3][4][5][6][7][8][9][10], labels [11][12][13][14][15][16][17], signs and markings, protective films [12,14,15], assembly operations [4,11,12,[18][19][20][21][22], as well as in dermal dosage systems for pharmaceutical applications [2,6,7,[10][11][12]17,[23][24][25][26][27] and biomedical electrodes [28]. Over the last 60 years or so, the development of acrylic pressure-sensitive adhesives has made tremendous progress, so much so that both manufacturers of pressure-sensitive adhesive articles and their adhesive suppliers now use sophisticated equipment and precise methods to study pressure-sensitive adhesive performance: tack, adhesion and cohesion.…”

“…The first two parameters are directly proportional to each other but are inversely proportional to the third. The performance of PSAs, such as tack, peeling and shear, are to a large extent determined by the method of polymerization, crosslinking process and last but not least the type and quantity of the crosslinking agents added to the acrylic PSA [4,7,12,17,27,32]. The common technologies for manufacturing pressuresensitive adhesives include the following kinds of acrylic pressure-sensitive adhesives (PSAs): solvent-based acrylic PSAs-the adhesive compounds are polymerized in solvent and cast onto the web and the solvents are dried off after coating, leaving behind the functional adhesive [11,12,19,21,31,33]; water-borne acrylic dispersion PSAs-the adhesive compounds are polymerized in water and then applied to the web, and, next, the water is dried off, leaving behind the functional adhesive; solvent-free acrylic PSAs in the form of typical hot melts, LVS (low viscosity systems) and photoreactive prepolymers.…”