Tackifying Resin Research Articles

Evaluation of the effect of different preparation processes on the road performance of thermoplastic resin modified porous asphalt mixtures

In order to evaluate the effects of three preparation processes, namely dry process (DP), wet process (WP) and wet/dry mixing process (MP), and resin high viscosity modifier (RHVM) on the road performance of porous asphalt mixtures, the frequency scanning, multi-stress creep recovery, and bending beam rheometer tests were used to analyze the rheological performance of resin-modified high viscosity asphalt under different processes. Uniaxial compression, Wheel tracking, Semi-circular bending and Freeze-thaw indirect tensile tests were used to test the properties of resin-modified porous asphalt mixtures under different processes. The commonly used TAFPACK-Super (TPS) modifier was a control group. Finally, the changes in the microscopic morphology characteristics and chemical composition were used to illustrate the enhancement mechanism of resin modifiers. The results showed that the high-temperature deformation resistance and low-temperature cracking resistance of RHVM modified asphalt prepared by DP and MP are weaker than that of the WP. Compared to the RHVM(WP), the Jnr(3.2) of RHVM(DP) and RHVM(WP) decreased by 14.3% and 63.8%, the strength modulus of RHVM(DP) and RHVM(MP) increased by 21.5%, 28.0% and the creep rate decreased by 2.37%, 4.45%, respectively. As for the performance of asphalt mixture, compared to the RHVM(WP) asphalt mixture, the dynamic stability of RHVM asphalt mixture prepared by the DP and MP decreased by 17.3–18.2%, σs and εs of RHVM(DP) and RHVM(MP) increased by 15–35% and 21–29%, respectively. The water stability of RHVM(DP) asphalt mixtures was better than that of RHVM(WP) when the mixing time reached 180 s. RHVM(WP) asphalt mixtures have superior low-temperature cracking resistance, comparable water stability, and slightly poorer high-temperature stability than that of TPS(WP) asphalt mixture. Microscopic morphology observation found that some modifier particles and asphalt binder did not realize effective mixing under the DP and MP, and infrared spectroscopy results confirmed that TPS modifiers are mainly physically co-mingled with asphalt, while the tackifier resin in the RHVM reacts with the asphalt to form new functional groups to increase the viscosity of the asphalt.

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

Improving the adhesion and tack of pressure-sensitive adhesives (PSAs) in the absence of tackifier resins or fillers remains an ongoing challenge.

Preparation of UV Debonding Acrylate Adhesives by a Postgrafting Reaction.

UV debonding acrylate adhesive (UDAA) plays a crucial role in the semiconductor industry, where its excellent adhesion is required to ensure the stability of silicon wafers and leave no residue on the surface after UV irradiation. The necessary UV debonding is achieved through the formation of rigid networks by the reactions of all the vinyl groups in the system. Acrylate copolymers with vinyl groups are typically obtained by the grafting reaction of isocyanate with a side-chain hydroxyl comonomer. However, these grafting reactions easily fail due to early cross-link formation. In this study, we illustrate a straightforward method for preparing UDAA by conducting a postgrafting reaction after one-step mixing of isocyanate functional monomer (IPDI-H) and hydroxyl acrylate copolymers (BA-H), thereby skipping the abovementioned vinyl grafting process. The chemical structures of the synthesized IPDI-H and BA-H were confirmed using Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (1H-NMR) analysis. Gel permeation chromatography (GPC) was employed to determine their molecular weights, while differential scanning calorimetry (DSC) was used to determine their glass transition temperatures. The postgrafting reactions successfully introduced vinyl groups onto the polyacrylate copolymer chains, resulting in high bonding strength during use and a significant decrease in peeling strength after UV irradiation. Rheological methods, including the three-interval thixotropy test (3ITT) and tack test modes, were employed to characterize a series of acrylate UV debonding adhesives. The recovery percentage of the storage modulus in the 3ITT mode indicated that a 0.6 wt% isocyanate curing agent made the UV debonding adhesives resistant to deformation. From the maximum normal force in the tack test mode, it was found that UDAA with 10 wt% PETA monomer and 30 wt% C5 tackifying resin exhibited excellent combined adhesion and debonding properties, which were further confirmed by peel strength tests. Microscope images of the wafer surfaces after removing the adhesive tapes demonstrated the excellent UV debonding properties achieved after 40 s of UV irradiation through the postgrafting reaction. The prepared UDAA has excellent properties; the peel strength can reach 15 N/25 mm before UV irradiation and can be reduced to 0.5 N/25 mm after ultraviolet irradiation. This research establishes a comprehensive method for understanding and applying UDAA in various applications.

Preparation and performance analysis of high-viscosity asphalt containing high-content SBS and crumb rubber by oxygen-free high-temperature treatment

Styrene-butadiene-styrene (SBS) and crumbed rubber (CR) are widely used for asphalt binder modification in the field of road materials. Especially, the high-viscosity asphalt with high-content SBS/CR modifiers has been applied for constructing the porous pavement and ultra-thin overlay. However, the workability of the SBS/CR modified asphalt still needs to be improved due to many unswollen polymer particles in the blended system. This work aims to propose an oxygen-free high-temperature treatment method to reduce the viscosity of SBS/CR-modified asphalt at construction temperature for better workability. Viscosities at 60 °C and 180 °C were tested to obtain the content of SBS, CR, and tackifying resin for high-viscosity asphalt; multiple physical tests were conducted to obtain acceptable heating temperature, initial pressure, and reacting time; the two high-viscosity asphalt binders cured under various conditions were compared through physics, chemistry, and rheology properties. The results show that the 70# asphalt incorporating 10% SBS, 6% CR, and 9% (by weight of asphalt binder) resin can prepare ideal high-viscosity asphalt binders. After high-speed shearing, it was recommended that CR-SBS-asphalt blends be cured in the reactor at the initial pressure of 3 MPa and temperature of 200 °C for 45 mins. The improved reaction conditions increased light components in a homogeneous and formed a stable modified asphalt blended system. Hence, the low-temperature performance and workability were improved, despite weakening the rutting resistance, which was still excellent at the high temperature.

Development of cardanol-derived epoxidized and Si-modified pressure-sensitive adhesives (PSAs)

This research attempts to create a pressure-sensitive adhesive (PSA) from cardanol as an outset material. The two kinds of formulations were established; the first scheme followed the epoxidation of cardanol, dihydroxylation, and PSA development. In the latter system, cardanol was pretreated with dichlorodimethysilane (DCDMS) in the second scheme, continuing the same procedure to obtain PSA resin. The chemical nature and structure confirmation were done using FTIR and NMR spectroscopy, hydroxyl value, epoxy equivalent weight (EEW), etc. To evaluate PSA resin's crystallinity, thermal stability and hydrophilicity the film was separately obtained for both the schemes by curing whereas to obtain PSA tapes the obtained PSA and tackifying resins were applied onto PET sheets. XRD analysis showed a decrease in the degree of crystallinity after incorporating DCDMS. The gel content values decreased, whereas the water absorption values increased, which could be related to the increase in the hydrophilic nature of PSA with an increasing number of tacky sites. TGA and DSC showed the formation of a high amount of char yield (∼31%) and a higher Tg (−37.72 °C) in Si containing film. The probe tack, peel strength, and shear strength values were high for the formulation with equal amounts of PSA and tackifying resin. Finally, the contact angle measurements showed that the hydrophobicity of film was also improved after incorporating DCDMS. The materials resembling PSA tape and including only small amounts of tackifying resins and crosslinkers displayed the ideal characteristics with satisfactory results.

Influence of Resins on the Structure and Dynamics of SBR Compounds: A Solid-State NMR Study

The tackifying effect of resins used in the tire industry highly depends on the compatibility and interaction strength with the rubber matrix. Here, uncured and cured styrene/butadiene rubber compounds, either in the presence or absence of a hydrocarbon aromatic tackifying resin, were studied by means of high-resolution and time-domain solid-state NMR (SSNMR) techniques to investigate resin/polymer interactions and the effect of the resin on the dynamics of polymer chains. 13C direct excitation and cross-polarization spectra, combined with low-field measurements of 1H T1 and analysis of 1H on-resonance free-induction decay, provided information on the dynamic heterogeneity of the samples and the degree of mixing between the resin and the rubber matrix. Moreover, 1H T1 and T1ρ relaxation times at variable temperatures were used to investigate the effect of resin on both segmental dynamics activated at the glass transition and collective polymer dynamics. SSNMR findings were discussed in relation to crosslink density and Tg data. The obtained results show that the resin is intimately mixed with the polymer, while maintaining its rigid character. A slowdown of segmental dynamics, related to an increase in Tg, was found as a consequence of resin addition, while no effect was evidenced on fragility and collective polymer dynamics.

Evaluations of Asphalt-Based Sealant Used in Concrete Caulking: Rheology, Adhesion Properties, and Microstructures

A concrete expansion joint can be damaged due to certain conditions. The performances in terms of temperature sensitivity and adhesion of used sealant materials in concrete caulking have strong relations to the joint service life. In this work, a composite-modified asphalt-based sealant (AS-M) with added styrene-butadiene-styrene (SBS), crumb rubber (CR), and tackifier resin (TR) modifiers was prepared, and its microstructure, high-temperature viscoelasticity, low-temperature crack resistance, and adhesion properties were evaluated, with two commercial finished sealants (AS-A and AS-B) as a reference. Specifically, Fourier transform infrared spectroscopy (FTIR) was used to analyze the chemical compositions of asphalt sealants, and the results showed that the physical blending and chemical reactions coexisted in the self-prepared sealant. A good compatibility and continuous structure for each sealant could be observed by fluorescence microscopy (FM). A dynamic shear rheometer (DSR) experiment was conducted to characterize the viscoelastic properties at high temperatures. The self-prepared sealant obtained the highest complex modulus, phase angle, and deformation resistance ability; the composite modifiers showed an outstanding modified effect. The glass transition temperature (Tg) was measured by dynamic mechanical analysis (DMA) testing. The Tg value of the self-prepared sealant was similar to that of the commercial sealant with SBS modifiers, whereas the stress relaxation modulus at a low temperature of the self-prepared sealant was the lowest, indicating that the combination of the modifiers made it obtain a better stress relaxation ability at low temperatures. The self-prepared sealant possessed the best interface adhesive capacity between sealant and aggregate based on surface free energy theory. The experimental results showed that the asphalt sealant modified by SBS/CR/TR has excellent performances in various properties and can be used for concrete caulking.

Properties and mechanism of SBS/crumb rubber composite high viscosity modified asphalt

Previous studies have shown that traditional modified asphalt is difficult to meet the requirements of road quality at the requirements of permeable pavement quality at complex service environments. SBS/crumb rubber composite high viscosity modified asphalt(SBS/CR) was prepared by adding tackifying resin and other modifiers. Standard tube separation tests and rheological results showed that the SBS/CR has better high-temperature performance and storage stability. Atomic force microscopy (AFM) results concluded that the modifiers formed a stable network structure in asphalt system, restricting the free movement and diffusion of asphalt molecules. Asphalt molecules undergo phase changes in a small range, resulting in a "Bee structure" with a large number, small area, and uniform distribution, which improved its surface roughness. Fourier infrared spectroscopy (FTIR) and scanning electron microscope (SEM) analyses confirmed the modification mechanism includes both chemical reaction and physical modification. The tackifying resin was mainly combined with the asphalt binder in the form of physical fusion. Compared with matrix asphalt, the internal structure of the SBS/CR was more stable, the heat absorption area became smaller, and the thermal stability was improved.

Combustion kinetics and fuel performance of tackifying resins by TG-FTIR and DFT analysis

Combustion kinetics and fuel performance of tackifying resins such as glycerol ester of colophony (GEC), glycerol ester of hydrogenated colophony (GEHC), C9 petroleum resin (C9PR) and hydrogenated C9 petroleum resin (HC9PR) were studied. Non-isothermal thermal analysis was performed in an air atmosphere, and the combustion characteristic, kinetic and thermodynamic parameters were calculated. Results show that all the resins studied have good combustion performance and environmental characteristics, and their experimental calorific values are 1.15–1.54 times of standard coal-equivalent (29.31 MJ/kg), indicating that tackifying resins and their corresponding wastes are promising fuel for generating energy. Furthermore, based on the isoconversional and master plots methods, it was found that the combustion of different resins was a kinetically complicated reaction, but the R3 model had an acceptable fitting effect in the whole combustion process. TG-FTIR and density functional theory (DFT) results demonstrate that colophony-based resins tend to degrade/burn the branched chains first and then the tricyclic phenanthrene structures, while petroleum resins degrade/burn the CC bonds on the backbone first and then the aromatic compounds, and the volatiles are mainly composed of H2O, CH4, CO2, CO, aromatic compounds and carbonyl derivatives.

Natural rubber-based cushion gum compound formulation at various type and dosage of rubber processing oil and tackifier resin

Cold retreading technique dominates retreaded tire manufacturing process. The technique applies rubber cushion gum compound as adhesion medium to bond new tread with a worn old tire. High-quality cushion gum compound mainly requires good adhesive strength. Tackiness of the rubber compound can be improved by addition of tackifier resin and rubber processing oil (RPO). The research was aimed to evaluate the performance of various types and dosages of tackifier resin and bio-based RPO to physic-mechanical properties of cushion gum. A method in the manufacture of natural rubber-based cushion gum compound was in accordance with ASTM D 3182. Cushion gum rubber compound formula was designed by using bio-based RPO such as pine tar oil at 5 and 12 phr and three types of tackifier resin such as rosin resin, phenolic resin, and hydrocarbon resin at 3 and 7 phr. Petroleum-based RPO and commercial cushion gum were selected as reference material. Curing characteristic and physic-mechanical properties test results were used as a reference to determine cushion gum quality. The observation during experiment indicated that natural rubber-based cushion gum compound formulated with addition of 5 phr rosin resin and 5 phr pine tar oil (code ZH4) has the closest curing characteristic and physic-mechanical properties to commercial cushion gum.

Preparation, Performance, and modification mechanism of high viscosity modified asphalt

A type of high viscosity modified asphalt (HVMA) with excellent performance was prepared by mixing a certain amount of SBS modifier, tackifying resin, stabilizer, and plasticizer into the base asphalt (BA) to meet the performance requirements of porous asphalt pavement. The influence of each modifier on the performance of composite modified asphalt was studied according to the basic physical performance test of asphalt, and the appropriate amount of each modifier was determined. The HVMA, BA, SBS/tackifying resin modified asphalt, and domestic high viscosity asphalt (HVA) were tested with a dynamic shear rheometer. The high temperature rheological properties of HVMA were evaluated by comparative analysis. The modification mechanism of HVMA was analyzed by Fourier transform infrared spectroscopy, scanning electron microscopy, and thermogravimetry/differential scanning calorimetry. Test results show that the 7% SBS modifier and 4% tackifying resin are the appropriate proportions. HVMA has excellent high temperature anti-rutting performance and anti-permanent deformation ability, which is not inferior to that of HVA. In the modification of HVMA, the modifier and BA are mainly physical blending; however, chemical reactions also occur. The modifier fully swells and evenly disperses in the asphalt, and the high temperature stability of the modified asphalt is effectively improved.

APPLICATION OF CALIXARENE DERIVATIVES AS TACKIFIER RESIN IN RUBBER COMPOUNDS FOR TIRE APPLICATIONS

ABSTRACT The effect of p-tert-Butylcalix[4]arene on rubber-nylon-6 fabric and rubber-metal bead wire adhesion strength was quantified. For this purpose, two typically used rubber compounds were employed for two reinforcing motorcycle tire components: ply and bead. The standard pull-out tests of rubber–fabric and rubber–metal showed improvements in adhesion strength by incorporating p-tert-Butylcalix[4]arene into rubber compounds. However, the maximum values of adhesion force to pull the polyamide fabrics and brass-coated metal wires out of the rubber compounds were observed when only 1.0 phr of p-tert-Butylcalix[4]arene was used. The adhesion performance of both fabric and metal wire decreased with higher loading amounts of p-tert-Butylcalix[4]arene. The effect of a commercial phenolic tackifying resin was also evaluated in bead compound. Very similar adhesion results to p-tert-Butylcalix[4]arene were obtained when using 1.0 phr phenolic resin.

Effect of tackifier resin and non-rubber components on adhesive property of natural latex

The objective of this study is to better understand the adhesive property of natural latex using phenolic resin at different ratios. Whole natural latex (WNL) and deproteinized natural latex (DPNL) are used. By increasing the resin ratio, the total solid contents (TSC) and viscosity for both types of latex increase. Interestingly, DPNL presents better adhesive properties than WNL for a given resin ratio. The phenolic resin at 3 phr gives the best adhesive property of latex. Beyond this resin ratio, the adhesive property decreases. Nevertheless, the phenolic resin can foster the flow properties in latex during the aging time, thus increasing the adhesive property of latex.

Hot-melt pressure-sensitive adhesives based on SIS-g-PB copolymer for transdermal delivery of hydrophilic drugs

SIS-g-PB copolymers were successfully synthesized by grafting living polybutadiene (PB) lithium macroanions onto epoxidized SIS copolymers. Their molecular structures and thermal properties were characterized by TGA, 1H-NMR and DSC, respectively. SIS, epoxidized SIS (ESIS) and SIS-g-PB copolymers were melt-blended with tackifiers to develop hot-melt pressure-sensitive adhesives (HMPSAs), respectively (named of H-SIS, H-ESIS and H-SIS-g-PB). Their adhesive performances were measured in terms of 180° peel strength and holding power. A modified Franz type horizontal diffusion cell was used to carry out In vitro drug release experiments, in which geniposides were chosen as hydrophilic model drugs. The results showed that H-SIS-g-PB has two times as high a 180° peel strength as H-SIS. Meanwhile H-SIS-g-PB has a slightly lower drug cumulative release rate than H-ESIS. It is indicated that the PB branches not only could impart good adhesive performance to H-SIS-g-PB via improving the compatibility between the epoxidized main chains and tackifier resins but also provide release channels to hydrophilic drugs by retaining most of the epoxide groups in the SIS-g-PB copolymers.

Preparation and characterization of natural rosin stabilized nanoparticles via miniemulsion polymerization and their pressure-sensitive adhesive applications

A series of rosin stabilized nanoparticles were prepared by miniemulsion polymerization. The hydrophobicity of dehydroabietic acid (DA) from rosin or from DA derived acrylic monomer (AEDA) was employed to stabilize the monomer miniemulsions. Then miniemulsion polymerizations of these monomer miniemulsions were performed separately and achieved the rosin stabilized nanoparticles with a near-monodisperse spherical morphology, respectively. This approach can effectively incorporate DA or AEDA into polyacrylate miniemulsion. Herein, AEDA played a role as both costabilizer and reactant in miniemulsion polymerization, and high molecular weight AEDA-MMA copolymers were achieved. The introduction of rosin’s moiety also could afford its copolymers with an improved thermal stability and mechanical property. Unlike conventional usage of rosin derivatives as a tackifying resin in pressure-sensitive adhesives (PSA), AEDA served as a hard component and improved the holding power of PSA, which opens a new platform for the using of rosin.

Investigation of the Mechanical Properties of a Pressure-sensitiveAdhesivePart 1 Analysis of SIS/C5 Resin Tackifier System by UsingRetardation Spectrum

Investigation of the Mechanical Properties of a Pressure-sensitiveAdhesivePart 1 Analysis of SIS/C5 Resin Tackifier System by UsingRetardation Spectrum

EFFECT OF FURFURAL ON THE PROPERTIES OF NATURAL LATEX: POSSIBILITY FOR ADHESIVE APPLICATION

ABSTRACT Normally, the properties of natural latex are not stable, for example, viscosity and volatile fatty acids, due to the nonrubber components that affect the quality of the latex. The objective here was to develop and compare the adhesive properties of natural latex by using furfural at different ratios. Concentrated natural latex (60% rubber) with a high ammonia rate was used, and two types of furfural were used: synthetic furfural and natural furfural from sugarcane bagasse. The phenolic resin was also compared as a tackifier resin. We found that increasing the furfural concentration in natural latex increased the viscosity of the latex. However, for a given concentration, furfural and phenolic resin gave similar adhesion properties in natural latex. Furfural at 10 parts per hundred of rubber gave the best adhesive property of natural latex. Beyond this furfural concentration, the natural latex became solid. There were no significance differences in adhesion properties between synthetic and natural furfurals in the natural latex. The relationship between viscosity and adhesive properties of the natural latex with furfural is proposed. This research shows the potential to develop an eco-friendly natural adhesive with furfural that has good quality and no dangerous solvent.

Simultaneous determination of the styrene unit content and assessment of molecular weight of triblock copolymers in adhesives by a size exclusion chromatography method.

The content of styrene units in nonhydrogenated and hydrogenated styrene-butadiene-styrene and styrene-isoprene-styrene triblock copolymers significantly influences product performance. A size exclusion chromatography method was developed to determine the average styrene content of triblock copolymers blended with tackifier in adhesives. A complete separation of the triblock copolymer from the other additives was realized with size exclusion chromatography. The peak area ratio of the UV and refraction index signals of the copolymers at the same effective elution volume was correlated to the average styrene unit content using nuclear magnetic resonance spectroscopy with commercial copolymers as standards. The obtained calibration curves showed good linearity for both the hydrogenated and nonhydrogenated styrene-butadiene-styrene and styrene-isoprene-styrene triblock copolymers (r=0.974 for styrene contents of 19.3-46.3% for nonhydrogenated ones and r=0.970 for the styrene contents of 23-58.2% for hydrogenated ones). For copolymer blends, the developed method provided more accurate average styrene unit contents than nuclear magnetic resonance spectroscopy provided. These results were validated using two known copolymer blends consisting of either styrene-isoprene-styrene or hydrogenated styrene-butadiene-styrene and a hydrocarbon tackifying resin as well as an unknown adhesive with styrene-butadiene-styrene and an aromatic tackifying resin. The methodology can be readily applied to styrene-containing polymers in blends such as poly(acrylonitrile-butadiene styrene).

Atomic force microscopy investigation of phase morphology correlated with adhesive properties for modified telechelic natural rubber based-pressure sensitive adhesive

Atomic force microscopy (AFM) is a powerful technique to determine phase morphology and surface mechanical properties of materials. In this research natural rubber was degraded and grafted by malelic anhydride before modification with 3-amino-1,2,4-triazole to obtain modified telechelic natural rubber or modified TNR. It was then blended with cumarone-indene resin at 10, 30, and 50 phr, acting as tackifier. Phase morphology and surface topography were investigated by intermitted AFM. The results showed that tackifier enriched domains were clearly observed in modified TNR matrix after added 30 and 50 phr and the domain sizes were approximately to be the order of micrometer (5–10 µm) which it increased with increasing tackifier content. The intermolecular hydrogen bonding interaction between tackifier and modified TNR was observed by attenuated total reflectance Fourier transform infrared spectroscopy. The adhesive properties (loop tack, peel, and shear strength) were governed by the size of tackifier enriched domains, surface mean roughness and compatibility or interaction between modified TNR rubber and cumarone-indene tackifier resin.

Water-based adhesive formulations for rubber to metal bonding developed by statistical design of experiments

Waterborne adhesives for rubber to metal bonding have been available since 1990. However, published information about their formulation has been limited, as proprietary restrictions are exercised by companies. As a consequence, the way these adhesives interact with substrates has not been studied extensively. With the aim of investigating the effect the components of a waterborne adhesive have on rubber to metal bonding, fractional factorial and surface response methodologies of design of experiments were employed in this study. Twenty six formulations were prepared with a polychloroprene latex as the adhesive polymer. Viscosity, wettability and non-volatile solids content were measured with each liquid adhesive, while the mechanical strength was evaluated by applying a tensile mechanical stress over cured solid adhesive films. Adhesion properties were evaluated by using a single lap-shear test on metal to metal joints and a pull-out test on rubber to metal joints. The results showed that the components with the largest relative influence on cohesive and adhesives forces were tackifier resin, silicon dioxide and polychloroprene latex type. In order to better understand the contributions of these variables, mathematical models correlating them with the response variables were obtained. This study is valuable in explaining how, through statistical methods, a waterborne adhesive for rubber to metal bonding can be formulated with a reasonably low number of experiments.