Synthesis of polyurethane acrylates by hydrogenated castor oil and dimer‐based polyester diol and study on pressure‐sensitive adhesive

Abstract

Synthesis of polyurethane acrylate (PUA) and preparation of the UV-cured pressure-sensitive adhesives (PSA) are reported. Molecular weight (M w ) (by gel permeation chromatography) and viscosity (*) of PUA were measured. Characterization of PUA and PSA before and after UV-curing was made by FTIR. Increase of the hydroxyls from hydrogenated castor oil/hydroxyls from dimer-based polyester diol (OH HCO /OH Diol ) ratio decreased the M w and * value of PUA. Dynamic viscoelastic properties (by dynamic rheological spectrometer) and performance of the UV-cured PSA were also studied. Increase of the OH HCO /OH Diol ratio increased the storage modulus (GЈ), the loss modulus (GЉ), and complex viscosity (Eta*) of the UV-cured PSA, which, in turn, enhanced holding power and shear adhesion failure temperature (SAFT) and yet decreased peeling strength. Substitution of OB for DBTDL depressed the M w and * value of PUA, while the GЉ and Eta* values of the UV-cured PSA were elevated, which, in turn, increased the holding power and SAFT and yet depressed the peeling strength. Elevation of the tackifying resin content depressed the GЈ, GЉ, and Eta* values of the cured PSA and yet increased glass transition temperatures (T g ) of PSA, measured by differential scanning calorimetry. Peeling strength of PSA elevated as increasing the tackifying resin, while the holding power and SAFT fell.

Synthesis and surface modification of sunflower oil‐based non‐isocyanate polyurethane: Physicochemical and antibacterial properties

“…Alternatively, the cross‐linked NIPU (24 h) degradation proceeds in three stages at 220.6, 339.7 and 403.8°C. These differences may be related to an increase in thermal stability due to crosslinking and are similar to those reported for other NIPUs in the literature, but temperatures are lower than those of conventional thermoset PUs 82,83 . The first stage at 220.6°C is associated to the low breaking energy of the CN bond of hydroxy urethanes 84 .…”

“…Non-crosslinked NIPU (0 h) has a maximum degradation temperature of 222.5 C. Alternatively, the crosslinked NIPU (24 h) degradation proceeds in three stages at 220.6, 339.7 and 403.8 C. These differences may be related to an increase in thermal stability due to crosslinking and are similar to those reported for other NIPUs in the literature, but temperatures are lower than those of conventional thermoset PUs. 82,83 The first stage at 220.6 C is associated to the low breaking energy of the CN bond of hydroxy urethanes. 84 The second stage at 342.0 C is related to the degradation of aliphatic hydrocarbon structures and hydroxyl functions of the urethane.…”

Role of the Soft and Hard Segments Structure in Modifying the Performance of Acrylic Adhesives Modified by Polyurethane Macromonomers

“…Usually, PU-acrylic PSAs were prepared by modifying acrylates with polyurethanes, which can simultaneously exhibit high hardness and flexibility characteristics of PU while retaining the advantages of acrylic PSAs themselves. For example, performance of adhesives has been strengthened; , the scope of application has been expanded; and the pollution to the environment has been reduced. , Therefore, studies on the modification of acrylic adhesives by polyurethanes provide an important approach to improve the performance of the adhesives. However, most of the studies on PU-modified acrylic adhesives regarded polyurethanes and acrylic adhesives as a whole during the synthesis or pursued new structures .…”

The synthesis and properties of binary acrylate oligomer mixtures and their blends with different soybean oil contents

“…The morphology and properties of these materials can be enhanced by the use of new monomer compositions or reactive solvents. [1][2][3][4][5][6][7][8] Thus, such materials were used in lithographic and coating applications, 9,10 plastic encapsulation to protect printed circuit boards, 11 ultraviolet-cured pressure-sensitive adhesives, 12 solid electrolytes for rechargeable lithium batteries, 13,14 nanocomposites, 15 polymer concrete, 16 and so on.…”