UV-curable pressure-sensitive adhesives derived from functionalized soybean oils and rosin ester

Abstract

Functionalized plant oils such as epoxidized soybean oil (ESO) are widely used in plastic industries as additives and are available for more value‐added applications. Pressure‐sensitive adhesive (PSA) derived from petroleum feedstocks has a huge market ranging from tapes to packaging. Here we show a sustainable PSA derived from ESO/dihydroxyl soybean oil (DSO)/rosin ester (Sylvalite) via UV‐initiated copolymerization. The ether crosslinks derived from cationic polymerization of ESO and copolymerization between ESO and DSO (or rosin ester) were demonstrated using 1H NMR, 2D 1H–1H COSY NMR, electrospray ionization mass spectrometry and thermal analyses (differential scanning calorimetry and thermogravimetric analysis). The PSA was formulated by modulating the ratio of ESO/DSO/rosin ester to achieve high performance. At a UV dose of 5.1–5.4 J cm−2 and 0.3–3% (w/w) of a photoinitiator, i.e. [4‐(2‐hydroxy‐1‐tetradecyloxy)‐phenyl]phenyliodonium hexafluoroantimonate, the PSA at a ratio (by weight) of 1:1:0.7 (ESO/DSO/rosin ester) recorded the highest peel and loop tack strength, which was comparable to a commercial PSA, Scotch Magic Tape, and showed much stronger shear strength (>30 000 min) than the commercial tape (10 000 min). The high‐shear rheological behavior and excellent thermal stability of the PSA were also demonstrated. © 2012 Society of Chemical Industry

Oxirane Cleavage Kinetics of Epoxidized Soybean Oil by Water and UV‐Polymerized Resin Adhesion Properties

“…7c). Copolymerization was believed to occur between epoxy groups of ESO and hydroxyl groups of DSO in forming ether linkages during UV-curing based on the previous study [9,17], although FTIR could not provide such information.…”

“…The first part of each label is the abbreviation for the PSA formulation, and the portion in parentheses indicates the composition and weight ratio of each component. The PSA component ratio was based on the optimized results as reported in our previous work [9]. No solvents were used in the PSA preparation.…”

Cationically UV-Cured Epoxy Composites

“…33 Multifunctionality in formulations is important not only to provide weathering protection or aesthetic appearance, but also for supplementary purposes as electrical conductivity, chemical stability, adhesion, and many more. [34][35] Among epoxides, only cycloaliphatic are commercially meaningful in UV-curing. This industrial significance corresponds not only to effective reactivity in cationic photopolymerization but also to their excellent adhesion, chemical resistance, and mechanical properties.…”

Photopolymerization Reactions: On the Way to a Green and Sustainable Chemistry

“…Renewable monomers/oligomers have been proposed and studied; e.g., (i) acrylates: acrylated vegetable oils [118], natural or naturally derived products (photocrosslinkable polylactides [119], ε-caprolactone [120,121], poly (lactide-co-ethylene oxide-co-fumarate) [122], poly(caprolactone-colactic acid) [123], methacrylate based gelatine derivatives [124], acrylate modified starch [125] and itaconic acid based photocurable polyesters [126]; (ii) epoxides: epoxidized sunflower [127,128], epoxidized soybean oil (ESO), linseed oil, vernonia oil or castor oil (see in [129]), limonene dioxide (LDO) [130] (limonene is a liquid terpene found in various volatile oils, such as cardamom, nutmeg and turpentine; LDO can be formed through oxidation of limonene by peracids), epoxidized natural rubbers [131], vegetable oils [132] and epoxidized fatty acid (EFA); or (iii) resins based on vegetable oil [133,134], soybean [135], rosin ester [136], tung [137] and palm stearin [138,139] and castor oil. The photopolymerization of such monomers is more or less efficient as a function of the chemical structure, the multifunctional character or the irradiation conditions.…”