Silicone Pressure-sensitive Adhesives Research Articles

Study of applying chalcedonite for silicone pressure-sensitive adhesives

Study of applying chalcedonite for silicone pressure-sensitive adhesives

The effect of neat and modified montmorillonite on thermal properties of silicone pressure-sensitive adhesives

Novel silicone pressure-sensitive adhesives containing modified montmorillonite were obtained, and subsequently, one-sided tapes were prepared. The novel adhesives were characterized by a higher tack, peel adhesion, and cohesion at room and elevated temperature when compared to the system without the filler. Adding modified fillers allowed to improve the thermal resistance of adhesive - the maximum operating temperature was in a range of 220–230 °C. The highest level of thermal resistance was obtained for acid-modified montmorillonite with a concentration of 0.1 M. It was found that the physical modification of silicone pressure-sensitive adhesives shifts the adhesive-cohesive balance towards cohesion.

The Effect of Pt-type Catalysts on Self-adhesive Properties of Silicone Pressure-sensitive Adhesives

AbstractUseful silicone pressure-sensitive adhesives (PSAs) have been prepared from a high solid silicone resin. Platinum catalysts and crosslinking compounds were used to obtain new self-adhesive tapes. The influence of catalysts and crosslinking compounds on the basic properties of self-adhesive tapes was tested, taking into account the compatibility of silicone composition. The obtained systems showed good self-adhesive properties, and high thermal resistance over 225 °C. The low viscosity of the compositions obtained relatively increases the application potential of self-adhesive tapes based on it. Moreover, the prepared compositions show the potential for further modifications, especially physical ones e.g. silicon powder. The obtained new tapes showed good self-adhesive properties and kept high thermal resistance over 225 °C. It is well known that silicone pressure-sensitive adhesives are a group of silicone adhesives for special applications. Due to their unique resistance to environmental conditions, temperature and chemical resistance, they are difficult to modify.

Influence of diatomite and its base modifications on the self-adhesive properties of silicone pressure-sensitive adhesives

The study examined how diatomite and its modifications affected the self-adhesive ability of silicone pressure-sensitive adhesives. To create adhesive composition for testing, fillers were added to a commercial silicone resin, which were then used to create new modified pressure-sensitive tapes. The resulting tapes were tested to determine their adhesion, tack, cohesion at room and elevated temperature, SAFT test (Shear Adhesive Failure Temperature), pot-life (viscosity) and shrinkage. The results obtained were compared with those of the unmodified tapes. The tests resulted in higher thermal resistance (225 °C) and lower shrinkage (0.1%). As a result, we can conclude that materials with thermal resistance with a slight decrease in other parameters were obtained.

Influence of Illite and Its Amine Modifications on the Self-Adhesive Properties of Silicone Pressure-Sensitive Adhesives.

Obtaining new silicone self-adhesive in the presence of modified illite has been described. The filler was modified with N,N,4-trimethylaniline. The effect of illite content and modification on functional properties (adhesion, cohesion, stickiness, and shrinkage) was determined. Additionally, the thermal resistance (the SAFT test) of obtained silicone pressure-sensitive adhesives was evaluated. For all the systems tested, an increase in thermal resistance and shrinkage decrease were noted. Moreover, only a slight adhesion and tack decrease was revealed. Such self-adhesives could be applied for joining elements operating at increased temperatures, e.g., in heavy industry.

Study of Applying Naturally Occurring Mineral Materials for Silicone Pressure-Sensitive Adhesives

Silicones are commonly used as adhesives when high-quality materials are required due to harsh environmental conditions such as high temperature, humidity, etc. To ensure high resistance to environmental conditions, including high temperatures, modifications of silicone adhesives are made using fillers. The characteristics of a modified silicone-based pressure-sensitive adhesive with filler are the focus of this work. Functionalized palygorskite was prepared in this investigation by grafting 3-mercaptopropyltrimethoxysilane (MPTMS) onto palygorskite (palygorskite-MPTMS). The palygorskite was functionalized using MPTMS under dried conditions. FTIR/ATR spectroscopy, thermogravimetric analysis, and elemental analysis were all used to characterize the obtained palygorskite-MPTMS. MPTMS loading onto palygorskite was also proposed. The results demonstrated that palygorskite's initial calcination favors the grafting of functional groups on its surface. New self-adhesive tapes based on palygorskite-modified silicone resins have been obtained. This functionalized filler allows for the improvement of the compatibility of palygorskite with specific resins for application in heat-resistant silicone pressure-sensitive adhesives. The new self-adhesive materials showed increased thermal resistance while maintaining good self-adhesive properties.

Influence of Acid-Modified Clinoptilolite on the Self-Adhesive Properties of Silicone Pressure-Sensitive Adhesives.

The preparation of a new "eternally alive adhesive" based on silicone pressure-sensitive adhesives with clinoptilolite is presented. Neat and acid-modified (i.e., treated with sulfuric acid (VI)) clinoptilolite was used. The effect of clinoptilolite acid treatment on the adhesive properties of pressure-sensitive adhesive tapes was tested. The obtained tapes exhibited increased thermal resistance when compared to the reference tapes. Despite introducing the filler, the pressure-sensitive adhesive tapes maintained good functional properties. The new self-adhesive materials show promising implementation potential where increased thermal resistance is required.

Organophilized Montmorillonites as Fillers for Silicone Pressure-Sensitive Adhesives.

In the presented work, organophilized montmorillonites (OMMT) with selected quaternary ammonium compounds (QAC) with different chemical structure ((trioctylmethylammonium chloride-A336, dimethyloctadecyl[3-trimethoxysilyl)propyl]ammonium chloride-D, cetyltrimethylammonium bromide-CTAB, 2-methacryloxyethyltrimethylammonium chloride-MOA) were obtained and used as fillers for physically modified silicone pressure-sensitive adhesives (Si-PSA). Before OMMT addition into Si-PSA matrix, they were analyzed via TGA and XRD techniques. Type of chemical structure of QAC affected d-spacing of OMMT. New self-adhesive materials were obtained based on prepared Si-PSA compositions by adding the obtained fillers to the polymer matrix. New tapes exhibit a good level of useful properties as adhesion, cohesion, and tack-the values did not change or slightly decreased; in addition, the tapes with addition of OMMT showed high thermal resistance reaching the measuring limit of the test equipment-to 225 °C.

Influence of UV on the self-adhesive properties of silicone pressure-sensitive adhesives

The paper presents the results of research on the UV radiation influence on the self-adhesive properties of silicone adhesives. The adhesives were obtained by cross-linking commercial resins (PSA 590, Q2-7566) at the temperature of 110°C, using different amounts (0–3 wt%) of bis(2,4-dichlorobenzoyl) peroxide. Self-adhesive properties of adhesives such as adhesion, tack, and durability before and after aging were determined. The adhesives showed stable self-adhesive properties, however, the PSA 590 adhesive had a higher maximum operating temperature than the Q2-7566 adhesive.

Influence of Nanoclay on the Thermo-Mechanical Properties of Silicone Pressure-Sensitive Adhesives.

This research was carried on newly obtained innovative materials-self-adhesive one-sided tapes based on silicone pressure-sensitive adhesives. In order to obtain tapes, the stable adhesive composition was subjected to physical modification by incorporating into it various amounts of selected silicon fillers. The produced pressure-sensitive adhesives were tested for viscosity and thermogravimetric analysis, as well as the manufactured tapes; i.e., peel adhesion, tack, cohesion at room and elevated temperature, SAFT test (shear adhesive failure temperature), and shrinkage. The prepared self-adhesive tapes retained their self-adhesive properties at a level close to the initial level while increasing the thermal resistance by 70-75 °C, reaching the level of 220-225 °C. The new self-adhesive materials have application potential and can be used as a material for special applications in the field of electrical engineering and heavy industry.

Development and evaluation of a drug-in-adhesive transdermal delivery system for delivery of olanzapine

ABSTRACT Objectives Olanzapine (OZP) is a safe and effective atypical antipsychotic drug used in treating schizophrenia and bipolar disorders. The dosage forms currently on the market for OZP are administered via oral or intramuscular routes. However, there are many problems associated with oral and intramuscular routes of drug administration. Thus, our aim was to develop a drug-in-adhesive transdermal delivery system (TDS) that can deliver OZP for 3 days. Methods We determined passive permeation, effect of oleic acid as chemical enhancer, and delivery of OZP across different skin types. Based on preliminary studies and saturation solubility of OZP in different pressure-sensitive adhesives (PSAs), we formulated and characterized solution-based TDS in acrylate PSA and suspension-based TDS in silicone and PIB PSA, with oleic acid as chemical enhancer. Results Acrylate solution-based TDS, silicone, and PIB suspension-based TDS delivered 58.97 ± 6.59 µg/sq.cm, 129.34 ± 16.59 µg/sq.cm, and 245.00 ± 2.51 µg/sq.cm, respectively, using in vitro permeation testing. PIB PSA suspension-based TDS met the 3 days desired target delivery. Skin irritation testing using In vitro EpiDermTM skin irritation test (EPI-200-SIT) kit found PIB TDS to be nonirritant. Conclusion The PIB PSA suspension-based TDS could serve as a potentially effective transdermal delivery system for olanzapine.

Influence of storage time on the useful properties of silicone pressure-sensitive adhesives

The influence of the storage time on the useful properties (cohesion, adhesion, stickiness) of silicone pressure-sensitive tapes (Si-PSA) was investigated. Two types of silicone resins PSA 529 and PSA 590 (Momentive, USA) were used and crosslinked with bis (2,4-dichlorobenzoyl) peroxide (DClBPO). There was no significant effect of tapes long-term storage (7 years) on their properties. The tapes based on PSA 590 resin were more resistant to aging than PSA 529.

Influence of modified attapulgite on silicone pressure-sensitive adhesives properties

Influence of modified attapulgite on silicone pressure-sensitive adhesives properties

Influence of cleaned granite dust on the properties of silicone pressure-sensitive adhesives

The influence of addition cleaned granite dust on self-adhesive products, such as self-adhesive tapes based on silicone pressure-sensitive adhesives was presented. The new way of waste management, is a very important issue in the modern world. The obtained self-adhesive materials were tested both in terms of the properties of adhesive compositions (pot-life test) as well as the influence on the operational parameters of the obtained self-adhesive tapes, such as adhesion, cohesion, stickiness or shrinkage. The obtained results are presented in the paper below.

Silicone pressure-sensitive adhesives with increased thermal resistance

The purpose of this work was to obtain single-sided tapes with different concentrations of kaolin and to check its impact on the self-adhesive properties of commercial adhesives. The most important self-adhesive properties were examined, such as tack, peel adhesion, shear strength, shrinkage, and thermal resistance. Tapes based on silicone PSAs with kaolin can be used in many branches of industry to bond elements operating at elevated temperatures, i.e., in aeronautics, aerospace including solar cells for satellites and space stations. There are few reports on one-sided adhesive tapes based on silicones with the addition of kaolin. However, taking into account the number of their potential applications, we did self-adhesive tests and explained how kaolin affects them. In addition, the reactivity of the crosslinking compound and silicone adhesive during the crosslinking process and the thermal effects of this process were also examined. In connection with the various applications of the obtained tapes, also the flammability and heat of combustion were tested, in accordance with applicable standards. As a result of the tests, one-sided self-adhesive tapes with new properties (increased temperature resistance, less shrinkage, and increased resistance to flammability) were obtained.

Effect of the addition of selected silicon fillers on Si- PSA shrinkage

The concept of shrinkage phenomenon is widely described in the available literature. With respect to pressure-sensitive adhesives (PSA) in general, the definition of shrinkage is understood to be "less than its original size" and is closely related to the crosslinking process and the effect of the crosslinker on the test adhesive. Shrinkage alongside adhesive properties (adhesion, tackiness) and mechanical (cohesion) is one of the most important characteristics of a self-adhesive adhesive. It is very important in terms of production when receiving, for example, decorative banners or self-adhesive films where crosslinked adhesive and thus shrinkage can affect the surface of the adhesive material and create deformations. In the case of PSA, the acceptable adhesive pressure shrinkage must not exceed 0.5 %. Contraction is an important criterion for assessing the aging resistance of PSA materials. There are no studies on the shrinkage of silicone pressure-sensitive adhesives in literature, but many references to carbon-based adhesives have been reported.

Conductive Electric Tapes Based on Silicone Pressure-Sensitive Adhesives

This paper assesses methods for the fabrication of single-sided electrically conductive tape. Silicone resin, dichlorobenzoyl peroxide, and various types of carbon fillers were used to prepare pressure-sensitive adhesives. Various carbon black and graphene filler concentrations in the range 1 to 25 wt.% were tested, whereas for carbon nanotubes the range was 0.25 to 10 wt.%. The adhesion, shear strength, tack, and shrinkage of the prepared tapes were determined. The most important property of the resulting tapes is their electrical conductivity. By using carbon black as a filler, it was possible to obtain a conductivity of 4.3 × 10−3 S/m, with carbon nanotubes 1.4 × 10−01 S/m and with graphene 5.9 × 10−3 S/m. Such electrically conductive silicone self-adhesive tapes are not yet commercially available on the market, but are expected to be useful in the electronic industry for the bonding of various materials. In the available literature provides no information about the self-adhesives tapes based on silicone pressure-sensitive adhesices which exhibit electrically conductive properties.

Impact of environmental conditions on silicone pressure-sensitive adhesives

Silicone pressure-sensitive adhesives are characterized by very good self-adhesive and functional properties. The first group includes: tack, adhesion and cohesion. No less important are the functional properties: maximum working temperature, shrinkage, resistance to external factors and yellowing. It is well known that silicone adhesives are materials for special applications due to their properties, namely surface tension, high UV transparency, good thermal stability, low intermolecular interactions or low surface tension. This paper attempts to investigate the influence of environmental conditions and PSA aging time on the most important functional and self-adhesive properties. This is an important aspect in terms of the use of this type of materials and their suitability for use. The tests were carried out after 1 h days and after a 6 month. To investigate the impact of environmental conditions samples (tapes and joints tapes with a steel substrate), they were conditioned in a climatic chamber simulating environmental conditions by 20 days.

Influence of Montmorillonite on the Properties of Silicone Pressure-Sensitive Adhesives: Preparation of a Double-Sided Tape Based on the Best Composition

Silicone pressure-sensitive adhesives were introduced in 1960. They exhibit good properties and are widely used. In this study, the nanofiller montmorillonite was added to such adhesives. Various loadings of this component were tested and their effects on properties such as adhesion, tack, cohesion at different temperatures, viscosity, and the maximum operating temperature were assessed. The adhesive with the optimal loading was selected, tapes were prepared, and the effects of the layer type on the self-adhesive properties were examined. Furthermore, double-sided tapes were fabricated with a new method. In this innovation, the two layers have distinct properties: one is crosslinked twice, the other once. The effects of this approach on the self-adhesive properties of the tapes were analyzed. The low shrinkage value and increased temperature resistance of tapes prepared by loading montmorillonite into pressure-sensitive adhesives demonstrate their potential usefulness in industrial production.

Nematic liquid crystal 4-cyano-4′-pentylbiphenyl functionalization of MWNTs for improved thermal and mechanical properties of silicone pressure sensitive adhesives

In this research, nanocomposite modified pressure sensitive adhesives (PSA) (5CB-MWNTs/PSA) with high mechanical and thermal properties were fabricated via nematic liquid crystal 4-cyano-4′-pentylbiphenyl (5CB) functionalized multi-walled carbon nanotubes (MWNTs). The results showed that 5CB interacted with MWNTs via non-covalent interactions e.g. π-π stacking, which not only improved the dispersion and orientation of MWNTs in a silicone PSA but also the compatibility between MWNTs and the silicone material. The tensile strength of 5CB-MWNT/PSA was increased to 14.5 MPa while the mass fraction of MWNTs was 1.0%, which was an enhancement of 943% over that of the MWNTs/PSA and 28 times greater than that of the neat PSA. In addition the thermal conductivity of the PSAs filled with the 5CB-MWNTs were improved to 1.28 W/(m•K) at a mass fraction of 10%, which was increased by 552% over that of the neat PSA and 231% over that of the MWNT/PSA. The resulting thermally conductive and mechanically applicable silicone PSA nanocomposites could be significant in a wide variety of pressure sensitive adhesive applications.