Tuning adhesion performance of an acrylic pressure‐sensitive adhesive using polysilsesquioxane‐acrylic core‐shell nanoparticles

Abstract

Surface migration of unmodified inorganic or polymer core‐inorganic shell nanoparticles has limited their application for improvement of pressure‐sensitive adhesives (PSAs) properties. The efficiency of utilization of modified inorganic nanoparticles with sticky polymer brushes was investigated to overcome this problem. For this purpose, polymethacryloxypropylsilsesquioxane‐acrylic core‐shell (CS) nanoparticles were synthesized and added to poly(methyl methacrylate‐co‐butyl acrylate) (MBC) acrylic PSA through latex blending. Using CS nanoparticles, a concomitant increase in the peel and shear strengths of the acrylic PSA was achieved, and also the limitation of surface migration of nanoparticles at high volume fractions was overcome. Moreover, CS nanoparticles acted as a compatibilizer for MBC chains, rich in methyl methacrylate (MMA) or butyl acrylate (BA). These MMA‐rich and BA‐rich chains were formed during the synthesis of MBC latex through batch emulsion copolymerization method, due to the difference in the reactivity ratio of BA and MMA radicals. The compatibility of CS nanoparticles with each of the components of MBC was systematically investigated in terms of grafting density, swelling ratio, and thermodynamic affinity and was correlated to the final properties.

Self-Cross-Linking Latex Pressure-Sensitive Adhesives: Preparation and Investigation on Adhesion, Linear Viscoelastic, and Nonlinear Large-Strain Properties

“…4,5 PSAs are soft viscoelastic materials that are capable of adhering to most surfaces under short contact time and low contact pressure while dissipating considerable energy during debonding. 6,7 Kaelble showed that the main reason for the proper adhesion of the PSAs is the occurrence of microcavitation and fibrillation during the debonding process. 8 To be specific, the PSAs in which microcavities form at the interface between the adhesive and the substrate during the debonding, followed by their expansion into the adhesive bulk to form fibrils, are capable of considerable energy dissipation.…”

“…4,10 These properties, frequently evaluated by the static shear test, 13 are important in applications where a PSA must withstand moderate levels of stress for a long time such as in bonding digital camera parts. 10 Approaches like taking advantage of nanoparticles, 6 comonomers (such as acrylic acid (AA), methyl methacrylate (MMA), styrene (St), etc. ), 4,14,15 and cross-linking agents 14 are used to improve the creep resistance of acrylic PSAs.…”

“…Although using a sufficient amount of nanoparticles such as cellulose nanocrystal, 16 silica, 17 and carbon nanotube 18 enhances the cohesion strength of the acrylic PSAs through restricting the dynamics of polymer chains, 4 their dispersion and distribution in the polymer matrix and prevention of their surface migration are of crucial importance which necessitate time-consuming nanoparticles surface modification step. 6,16 On the other hand, the usage of comonomers for increasing the creep resistance of the acrylic PSAs 4,14 is also accompanied by some consequences. Indeed, although at an optimal content of the conventional comonomers, a significant enhancement of creep resistance is obtained, and tack is adversely affected.…”

“…Although this low entanglement density of acrylic polymers (PBA and P2EHA) is a crucial parameter for fibrillation in peel and tack, it results in their low cohesion strength and creep resistance. , These properties, frequently evaluated by the static shear test, are important in applications where a PSA must withstand moderate levels of stress for a long time such as in bonding digital camera parts . Approaches like taking advantage of nanoparticles, comonomers (such as acrylic acid (AA), methyl methacrylate (MMA), styrene (St), etc. ), ,, and cross-linking agents are used to improve the creep resistance of acrylic PSAs.…”

Biosynthesis cobalt‐doped nickel nanoparticles and their toxicity against disease

“…The available physicochemical methods for the synthesis of nanoparticles are relatively expensive and toxic and also cause harmful effects on the nature (Ahmadi- Dehnoei & Ghasemirad, 2022;Naveenraj et al, 2018). In this regard, green synthesizing procedures implicate the usage of natural materials, such as plant (Dousari et al, 2023;Indhira et al, 2022), fungal (Ameen, al-Homaidan, et al, 2021), algae (AlNadhari et al, 2021) and bacteria (Ameen et al, 2020) extracts, to act as the trapping and reducing agents in combination with metals similar to nickel, which can merge into an interesting and valuable field in nanotechnology (Dehnoei & Ghasemirad, 2020).…”