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EN
Water dispersions are usually a colloidal system in which one of the phases is highly dispersed in a second of a continuous nature, called a dispersion medium (in this case it is water). Dispersal is also called the process of distraction and self- -disperse as such. Water dispersions of carboxymethyl starch are the basis for the preparation of many products that, due to their initial dispersion form, can be modified, e.g. by adding fillers such as biodegradable films that affect the rheological properties of the dispersion [1]. The carboxymethyl derivative of starch was synthesized for the first time in 1924. The carboxymethylation reaction has become one of the most important starch modifications used in the industry on a large scale. Carboxymethyl starch (CMS) is characterized by a good solubility in cold water and higher resistance to bacteria than unmodified starch [7–9]. The carboxymethyl starch is obtained by the reaction of carboxymethylation (etherification) of the alkaline starch consisting in the introduction of the substituents into the structure of the starch, by reaction with monochloroacetic acid sodium salt. This process is called Williamson’s synthesis and CMS with different degree of substitution can be obtained by means of the mentioned process [10, 11]. The degree of substitution of carboxymethyl starch has a significant influence on its rheological properties, water dispersion of CMS with DS = 0.87 showed five times higher viscosity than CMS with lower value of this parameter, i.e. 0.15. Water dispersions with an increase in the montmorillonite content showed a high viscosity increase (about twice the increase in viscosity with the addition of 3% by weight). In both cases, aqueous dispersions stored above one month may be subject to the environmental degradation. In addition, in cases of compositions containing MMT, a rapid drop in viscosity due to the montmorillonite sedimentation is observed [17]. Rheological research of water carboxymethyl starch dispersions has great importance for science and for the subsequent application possibilities of products obtained on their basis. The effect of fillers on viscosity, and thus on the possibility of mixing them with aqueous CMS dispersions, affects, for example, the production of biodegradable films based on CMS with MMT, where the film is obtained from an aqueous dispersion of CMS with MMT with the addition of glycerine and citric acid [22]. Moreover, water dispersion of carboxymethyl starch with the addition of montmorillonite can be used as an additive to drilling fluids, electro-reed liquids or foundry adhesives [17].
PL
Zbadano wpływ czasu naświetlania lampą LED na gotowe dostępne na rynku usług stomatologicznych kompozyty dentystyczne. Określono podstawowe właściwości utwardzonych kompozytów, takie jak wytrzymałość na ściskanie, moduł Younga, odkształcenie przy ściskaniu. Ponadto dla wszystkich badanych próbek określono organoleptycznie wygląd pękniętego kompozytu. Wydłużenie czasu naświetlania początkowo zwiększało, a następnie po uzyskaniu maksimum zmniejszało wytrzymałość próbek na ściskanie oraz zmniejszało wartość odkształcenia przy ściskaniu i moduł Younga.
EN
A com. dental composite was irradiated for 10-70 s to study the curing efficiency. Compressive strength, Young modulus and compression strain of the composite were detd. Organoleptic appearance of cracks in the composite was also obsd. The compression strain decreased during the irradn. but compression strength and Young modulus reached a max. after irradn. for 30 s and 20 s., resp.
3
Content available remote Palność wybranych silikonowych klejów samoprzylepnych
PL
Spośród wcześniej badanych samoprzylepnych klejów silikonowych (SI-PSA) wybrano te, które odznaczały się najlepszymi właściwościami użytkowymi (adhezją, kohezją oraz kleistością kompozycji) i zbadano ich palność poprzez określenie szybkości wydzielania się ciepła i dymu oraz zmiany masy próbki w funkcji temperatury, a także oznaczono ciepło spalania danych SI-PSA.
EN
Kaolin nanoparticles (5% by mass) as a filler and dichlorobenzoyl peroxide (1.5 or 2.5% by mass) as a crosslinking agent were added to com. silicone pressure-sensitive adhesives and selected adhesive compns. were coated on polyester carrier. The dried adhesive layers were thermally treated in accordance with the relevant stds. to det. the rates and amts. of heat and smoke released from the tested materials as well as their combustion heat values. The adhesion, cohesion and tack of adhesives were studied. The kaolin addn. resulted in significant redn. in rates and amts. of heat and smoke released from the tested adhesives and the value of their heats of combustion. On the other hand, it had a slight impact on their applicability.
PL
Otrzymano poliakrylanowe kleje samoprzylepne sieciowane promieniowaniem UV zawierające komercyjny fotoinicjator Visiomer 6976. Zbadano ich podstawowe właściwości samoprzylepne, takie jak adhezja, kleistość i kohezja w różnych temperaturach, w zależności od natężenia promieniowania UV-C oraz stężenia nienasyconego fotoinicjatora.
EN
A soln. of 2-ethylhexyl and Bu acrylates and CH2=CHCOOH in AcOEt was photopolymerized in presence of a com. thermal photoinitiator (benzophenyl methacrylate in CH2=CHMeCOOMe) and azoisobisbutyronitrile (0.1 and 0.2-1% by mass, resp.) for 3 h, dild. with i-PrOH and used for covering a polyester film. After vaporization of the solvent at 110°C for 10 min, the adhesives were irradiated with UV (dose 5-50 mJ/cm2).
EN
In this work for the first time, activated carbons were prepared from carboxymethyl film (low-cost carboxymethyl film waste), using chemical activation with potassium hydroxide. The samples were characterized by nitrogen adsorption-desorption at 77 K, XRD, SEM methods. The high values of the specific surface area and total pore volume were achieved and were equal to 2064 m2 /g and 1.188 cm3 /g, respectively. Waste from the film can be immediately utilized without CO2  production. This is the environmentally friendly way of waste utilization. Through this process, we can protect our environment. This study showed that the activated carbon obtained from carboxymethyl film waste can be used as a good adsorbent for CO2  adsorption.
6
Content available Samonaprawiające się lakiery
EN
The recent decade brought about new dimensions to materials developments; stimuliresponse materials capable of responding to internal or external stimuli. The ability of materials to autonomously self-heal is the most promising property [1]. The number of publications that appeared in the past decade concerning the self-repair of polymeric materials is quite extensive. They cover different fields of research, including thermoplastic and thermoset polymers, polymer composites, and coatings. The first ideas already started to develop in the 1990s, when scientists started to look at nature to solve the recurring problem of damage to materials [2]. The process of implementing a strategy of autorepair of a damage is a subject of increasing interest. One of the challenges for many of the already developed self- -repairing systems is to enhance the structural stability and mechanical properties of the materials. The first developed self-healing materials relied on microencapsulated healing agents within the bulk polymer [3]. Upon mechanical stress, the microcapsules were ruptured releasing agents that reacted with the catalyst in the polymer matrix to repair the damage [4–5]. Among many other crosslinking methods relying mainly on epoxy chemistry, ‘click’-based chemistry, the use of thiolene-based systems, as well as catalytic crosslinking reactions based on ring opening metathesis polymerization have found wide application in materials science. In the latter methodology, the catalyst present inside the matrix then promotes an autorepair reaction via ROMP. Thermosetting autorepair polymers which have been proposed so far include Grubbs’ first-generation catalyst; currently, the possibility of applying other ruthenium catalysts such as second-generation Grubbs’ catalyst and Hoveyda–Grubbs’ second-generation catalyst are under evaluation [3]. In addition to the aforementioned methods, you can also find self-healing coatings in the reaction of Diels-Alder. The self-healing concept envisages a similar recovery of material properties, such as fracture toughness, corrosion resistance, or conductivity, to improve the durability and reliability of the polymer materials. Damage due to impact, wear or fatigue initiates a healing mechanism that preferentially without external stimulus can recover any functionality. Researchers working in the field of self-healing polymeric materials mainly focus on high-end applications where the added value outweighs the cost of production. Such applications can, for example, be found in the transport sector, electronics, and structural materials. Car coatings, structural composites in airplanes, conductive polymers in sensors are only some examples of many targeted applications. Repair of damage in these materials is often laborious, not cost-efficient and only detected on the macroscopic level when it is too late. On the other hand, self -healing materials try to avoid macroscopic failure by responding immediately or at least fast enough to damage [1].
EN
Pressure-sensitive adhesives (PSA) are a group of adhesive-based macromolecular polymers which are characterized by good (satisfying the requirements of industrial) adhesion and cohesion; high temperature stability during use, excellent aging resistance and constant tear strength. In 1935, the concept of self-adhesive glue, wherein the obtained self-adhesive product of the invention R. Stanton Avery, was firstly developed. From many types of adhesives, the most common adhesives are acrylics pressure-sensitive adhesives [1–3]. In most cases, self-adhesive adhesives do not exhibit good conductive properties, whereas conductivity grades are classified in the group of insulators. In order to improve their conductive properties, studies have been conducted on the modification of polymers in adhesive compositions, where at least one of the components exhibited conductive properties (e.g. polymers with conjugated π-bonded polymers along polymeric chains). However, the best effects were obtained by adding conductive fillers such as metal (copper, aluminum), specially modified soot, nanotubes or graphene, carbon fibers, metallized glass and conductive fibers. This allowed the creation of electrically conductive compositions characterizing by conductivity in the range from 10–2 to 102 S/cm. This relatively high conductivity is the result of the percolation of conductive filler molecules into an insulating matrix or tunneling between electrically conductive molecules [10, 11]. Acrylate pressure-sensitive adhesives with conductive fillers have found a number of important industrial applications, especially in the electronics industry. Pressure- sensitive adhesives, such as self-adhesive tapes or adhesive films, are used as heating elements, sensors or conductive gums. Due to their good performance, they can be used to connect solar panels or glue small components in the microelectronics industry. They also can be used to discharge static charges from the surface – used as flexible drainage connections – especially in places where the spark is undesirable and can be dangerous. They are used as heating elements [10, 12, 27].
8
Content available remote Wpływ związku sieciującego na skurcz samoprzylepnych klejów silikonowych
PL
Otrzymano samoprzylepne kleje silikonowe z różną ilością nadtlenku 2,4-dichlorobenzoilu, użytego jako związek sieciujący. Zbadano wpływ ilości tego związku na właściwości silikonowych klejów samoprzylepnych, ze szczególnym uwzględnieniem skurczu filmu klejowego. Badania skurczu wykonano wg metody krzyżowej opracowanej w niemieckiej firmie BASF. Zwiększenie ilości środka sieciującego w kompozycji zwiększało kohezję i zmniejszało adhezję, kleistość oraz skurcz filmu klejowego.
EN
Silicone pressure-sensitive adhesives with various amts. of 2,4-dichlorobenzoyl peroxide (I) used as crosslinking agent were prepd. to study of its effect on shrinkage of the adhesive film. The tests were performed according to the cross-cutting German method. The addn. of I resulted increasing the cohesion and decreasing the adhesion, tack and shrinkage of the self-adhesive film.
9
Content available remote Wpływ proszku miedziowego na właściwości akrylanowych klejów samoprzylepnych
PL
Otrzymano zawierające proszek miedziowy akrylanowe kleje samoprzylepne PSA (pressure-sensitive adhesives) przewodzące prąd elektryczny. Zbadano wpływ ilości proszku miedziowego na właściwości adhezyjne klejów PSA oraz określono przewodność kompozycji zawierających miedź. Dodatek proszku miedziowego w kompozycji zwiększał kohezję i przewodność, a zmniejszał adhezję i kleistość filmu klejowego.
EN
Conductive acrylic pressure-sensitive adhesives were prepd. by addn. of Cu powder (3-50% by mass) and studied for elec. cond., cohesion, adhesion and tack. The addn. of Cu filler resulted in increasing the composite cohesion and cond. and in decreasing the adhesion and tack of the adhesive film.
EN
In our studies montmorillonite (MMT) was used as the heterogeneous, natural catalyst. This material was previously prepared by bentonite purification with help of the sedimentation method. The obtained catalyst was characterized by: XRD, SEM, BET and EDX. Catalytic tests with montmorillonite as the catalyst were performed with the natural terpene – R-(+)-limonene. This compound was oxidized with hydrogen peroxide and, moreover, in the separate process it was also isomerized. As the main products of limonene oxidation were detected: (1,2-8,9)-diepoxide, perillyl alcohol, carvone, carveol, 1,2-epoxylimonene and 1,2-epoxylimonene diol. In the isomerization of R-(+)-limonene were formed: terpinenes, terpinolene and p-cymene. Conversions of limonene in these processes reached 70–80%. The application of montmorillonite (the natural of origin) in the studied processes (oxidation and isomerization) is environmentally friendly, it allows to reduce the cost of the studied processes. The resulting products of the processes of oxidation and isomerization of R-(+)-limonene have many applications.
EN
Self-adhesives materials are materials that develop significant adhesive forces upon contact with a substrate without requiring a chemical reaction without leaving residues on the substrate. To exhibit this property, self-adhesives materials should have cohesive strength that is much higher than its adhesion strength to the substrate. Usually they are defined as a viscoelastic material, which in a solvent free state remains permanently tacky at room temperature. Mechanically, they are a soft, sticky substance; consequently, a supporting backing is often required to convert it into commercially useful forms, such as tapes and labels. Mounting mass are a special form of self-adhesives materials usually in similar to modelling clay form plasticizer after warming up in the fingers. They are characterized by the fact that it does not dry out and can be relatively easily peeled off. They are used, inter alia, for fastening light units (including posters) to dry surfaces (walls, tables). The first company producing them was the company Bostik, the product Blu-tray, the composition of which is the secret of the manufacturer, generally described as a mixture of synthetic rubber, not showing dangerous properties in normal applications. Currently it is known a lot of self-adhesive products in the form of plastic masses produced by industry names “Blu-Tac” (Bostik), “UHU tac patafix” (Uhu GmbH) or “Prott buddies” (Henkel). Preparation of novel mounting mass using composition silicone risen with trimethylopropane triacrylate crosslinking by the use of UV or LED radiation was presented. Their adhesive properties on various substrates and cohesiveness are determined using international standards. Obtained materials are characterized by excellent cohesion and enough adhesion.
PL
Masy montażowe w formie plastycznych mas klejących wielokrotnego użytku, podobne w konsystencji do plasteliny lub kitu, charakteryzują się tym, że nie wysychają i dość łatwo można je odkleić. Są używane między innymi do mocowania lekkich elementów (takich jak plakaty) oraz do suchych powierzchni (ściany, tablice). Pierwszą firmą produkującą je była firma Bostik pod nazwą produktu Blu-Tacka, którego skład stanowi tajemnicę producenta. Jest opisywany ogólnie jako mieszanina gum syntetycznych nie wykazująca niebezpiecznych właściwości w normalnych warunkach aplikacji. Obecnie znanych jest wiele produktów samoprzylepnych w postaci plastycznych mas produkowanych pod branżowymi nazwami „Blu-Tac” (Bostik), „UHU tac patafix” (Uhu GmbH) czy „Prott buddies” (Henkel), jednak ich skład chemiczny nie jest ujawniony przez producentów. Celem pracy było otrzymanie mas montażowych na bazie żywic silikonowych i triakrylanu trimetylolopropanu wykazujących znakomitą kohezję oraz wystarczającą adhezję do podłoży o zróżnicowanej energii powierzchniowej. Ponadto zbadano podstawowe właściwości otrzymanych mas montażowych, takie jak adhezja (do stali, polimeru i papieru) oraz kohezja w celu scharakteryzowania otrzymanych nowych materiałów samoprzylepnych oraz określono ich potencjalne możliwości aplikacyjne w porównaniu z istniejącymi już na rynku komercyjnymi masami montażowymi wiodących firm.
EN
Pressure-sensitive adhesives (PSAs) represent a system that actually dates back to the invention of the self-adhesive articles in 1935 when R. Stanton Avery produced the first coating unit using a wooden cigar box with two holes cut in the bottom. PSAs can be defined as a special category of adhesive which in dry form are permanently tacky at room temperature [2, 6–8]. Since 1960s, silicone pressure-sensitive adhesives have found many uses. They are used in industrial plants, as tapes for joining materials with low surface energy, as well as in the sectors of electrical and electronic, medical care, health care and automotive industry. For about 10 years there has been great interest in new uses for the silicone PSA, particularly for medical and industrial belts. The above examples describe a growing range of potential commercial applications of silicone pressure-sensitive adhesives [2, 7, 9–11]. In contrast to the pressure-sensitive adhesives organic silicone pressure-sensitive adhesives show much better performance by this well known it happened that are used to obtain self-adhesive materials for special purposes. Si-PSA usually consist of large segments of the silanol-functional silicone polymers, and silicone resins. Polymeric chains comprising the silicone resins include methyl and phenyl groups thus are very little reactive chemicals. In order to obtain the best adhesion-cohesion balance are used crosslinked thermally in a temperature range of 120–150°C by using organic peroxides. Peroxides most commonly used in industry benzoyl peroxide (BPO) and 2,4-dichlorobenzoyl peroxide (DClBPO). Silicone pressure- -sensitive adhesives are characterized by high flexibility of connections Si-O-Si, low impact intermolecular, low surface tension, excellent thermal stability and transparency for UV radiation, excellent electrical properties, high chemical resistance and weather resistance [2, 6, 7, 14]. In the available literature the montmorillonite and kaolin modified silicone pressure-sensitive adhesives which exhibited increased thermal resistance are reported. The thermal properties of adhesives compositions are better to compared with “pure” silicon composition without any filler [6, 12–14].
13
Content available Sieciowanie samoprzylepnych klejów silikonowych
EN
Pressure-sensitive adhesives (PSAs) represent a system that actually dates back to the invention of the self-adhesive articles in 1935 when R. Stanton Avery produced the first coating unit using a wooden cigar box with two holes cut in the bottom. PSAs can be defined as a special category of adhesive which in dry form are permanently tacky at room temperature [1–4]. Since 1960s, silicone pressure-sensitive adhesives have found many uses. They are used in industrial plants, as tapes for joining materials with low surface energy, as well as in the sectors of electrical and electronic, medical care, health care and automotive industry. For about 10 years there has been great interest in new uses for the silicone PSA, particularly for medical and industrial belts. The above examples describe a growing range of potential commercial applications of silicone pressure- -sensitive adhesives. Silicone pressure-sensitive adhesives typically consist of large segments of the silane-functional silicone polymers and silicone resins (MQ). It is well known that silicone pressure-sensitive adhesives because of their unique properties are special-purpose products. The combination of the properties of silicones such as high flexibility of connections Si-O-Si, low intermolecular interaction, low surface tension, excellent thermal stability and transparency for UV radiation, excellent electrical properties, high chemical resistance and weather resistance makes silicone adhesives have improved properties compared to other typical polymeric organic adhesives. Due to the low surface tension of silicone adhesives, adhesive is easily spread on the surface of various materials [4–9]. The properties of silicone pressure sensitive adhesives (Si-PSA) crosslinking thermally by organic peroxides (according to a radical mechanism) depend on the type and concentration of crosslinker used. Benzoyl peroxide (BPO) and 2,4-dichlorobenzoyl peroxide (DClBPO) are the most commonly used peroxides the industry. Increasing the content of BPO or DClBPO in a predominantly affects significantly increase the cohesion, while reducing the adhesion of tested adhesives [1, 5, 6]. With the market testing of pressure sensitive adhesives and literature studies clearly show that there were no studies to date on the process of UV-curing silicone pressure sensitive adhesives; and there is no sales sided adhesive tapes, silicone crosslinked by UV radiation.
14
Content available remote Wpływ nanocząstek na twardość i adhezję powłok uretanoakrylanowych
PL
Przeprowadzono badania lakierów na bazie uretanoakrylanów z różnymi nanocząstkami w celu poprawy jakości fotoutwardzonych powłok. Wszystkie próbki utwardzono lampami UV, przy różniących się znacznie czasach naświetlania, dawkach i natężenia promieniowania. Wszystkie te parametry znacząco wpływają na twardość i adhezję lakierów fotoutwardzalnych. Na podstawie wyników badań doświadczalnych określono warunki zastosowania komercyjnych nanocząstek oraz natężenia promieniowania w celu otrzymania uretanoakrylanowych powłok o wysokiej twardości i adhezji.
EN
Four nanoparticles-contg. coatings were prepd., UV cured and studied for hardness and adhesion. After addn. of nanoparticles, the hardness of the coatings increased under low UV radn. intensity (10 mW/cm²) and decreased under high UV radn. intensity (0.6 W/cm²).
PL
Otrzymano silikonowe kleje samoprzylepne z dodatkiem nanocząstek kaolinu. Przedstawiono wyniki badań wpływu stężenia nanocząstek kaolinu na wybrane komercyjne samoprzylepne kleje silikonowe. Zbadano odpowiednio wpływ dodatku 1, 3, 5 i 7% mas. kaolinu w odniesieniu do zawartości polimeru kleju silikonowego. Według międzynarodowych norm AFERA zbadano podstawowe właściwości modyfikowanych klejów samoprzylepnych, takie jak adhezja, kohezja i kleistość. Zwiększanie stężenia napełniacza powodowało pogorszenie kohezji i adhezji oraz wzrost lepkości kleju w czasie.
EN
Kaolin nanoparticles were added (1–7% by mass) as fillers to 2 com. Si-org. adhesives poured then onto a polyester film, cured with (Cl2C6H3COO)2 and studied for tackiness and adhesion by std. methods. The increase in the filler content resulted in decreasing the adhesion and tackiness of the adhesives.
EN
Hydrogels are a unique class of macromolecular networks that can hold a large fraction of an aqueous solvent within their structure. They are suitable for biomedical area including controlled drug delivery and for technical applications as self-adhesive materials for bonding of wet surfaces. This paper describes photoreactive self-adhesive hydrogels based on acrylics crosslinked using UV radiation. They are prepared in ethyl acetate through radical polymerization of monomers mixture containing 2-ethylhexyl acrylate (2-EHA), butyl acrylate (BA), acrylic acid (AA) and copolymerizable photoinitiator 4-acryloyloxy benzophenone (ABP) at presence of radical starter 2.2’-azobis-diisobutyronitrile AIBN. The synthesized acrylic copolymers were determined by viscosity and GPC analysis and later modified using ethoxylated amines. 4-acryloyloxy benzophenone (ABP) was used as crosslinking monomer. After UV crosslinking the properties of these novel synthesized hydrogels, such as tack, peel adhesion, shears strength, elongation and water adsorption were also studied.
PL
Silikonowe kleje samoprzylepne są wysokiej klasy klejami, które mogą być używane w szerokim zakresie temperaturowym, od –40 do 300ºC, jako taśmy lub etykiety samoprzylepne na różnego rodzaju podłożach, gdzie nie mogą być stosowane typowe PSA. Od 2000 r. obserwuje się wzrost zainteresowania możliwością nowych zastosowań dla PSA silikonowych, zwłaszcza takich produktów samoprzylepnych, jak taśmy medyczne oraz przemysłowe. Sieciowanie silikonowego PSA z grupami metylowymi oraz fenylowymi można przeprowadzić za pomocą nadtlenków organicznych w temp. pomiędzy 120 a 150°C. Taśmy dwustronne są bardzo zróżnicowane pod względem używanych nośników oraz rodzajów klejów samoprzylepnych i służą do łączenia ze sobą wielu rodzajów materiałów. W dostępnej literaturze nie ma doniesień o dwustronnych taśmach na bazie silikonowych PSA. Badane taśmy otrzymano przez dwustronne powlekanie nośnika. Otrzymane dwustronne taśmy samoprzylepne na bazie Si-PSA wykazują dobre właściwości fizyczne dla obu stron filmu klejowego w postaci odpowiedniej kleistości (tacku), odpowiedniej przyczepności (adhezji) oraz wysokiej wytrzymałości wewnętrznej (kohezji).
EN
Silicone pressure-sensitive adhesives are high-performance adhesives that can be utilized over a wide range of temperatures, from –40 to 300ºC. They are widely used in self-adhesives tapes and labels when application conditions or the nature of substrate surfaces surpass the performance boundaries of organic-based PSAs. Since the year 2000, there has been continuing interest in it of new uses for silicone PSAs, especially in applications such as medical and industrial tapes. The crosslinking of silicone PSAs with methyl or/and phenyl groups can be achieved thermally between 120 and 150°C by organic peroxide. Double-side tapes are highly differentiated in used carrier and pressure-sensitive adhesives; they are used for joining together the assembly of all kinds materials. In the available literature there are no reports about double-side tape based on silicone PSA. Tapes were obtained by double-side coating of the carrier. The resulting double-sided self-adhesive tape on the basis of Si-PSA exhibit good physical properties both sides of the adhesive film in a form suitable tackiness (tacku), sufficient adhesion (adhesion), and high internal strength (cohesion).
PL
Przedstawiono wyniki badań wpływu ilości barwnika Luconyl green 9360 na wybrane komercyjnie samoprzylepne kleje silikonowe. Zbadano odpowiednio wpływ dodatku 0,5–4% mas. barwnika Luconyl green 9360 na właściwości klejów. Zwiększanie stężenia barwnika powodowało pogorszenie kohezji i adhezji oraz wzrost lepkości w czasie. Dodatek zielonego barwnika był niezbędny w celu zastosowania powleczonego samoprzylepnego kleju silikonowego do łączenia dehezyjnych materiałów charakteryzujących się niską energią powierzchniową.
EN
Luconyl green 9360 dye was added to a com. Si pressuresensitive adhesives cured then with dichlorobenzyl peroxide on Si paper or steel substrates. The adhesive layers were studied for tack, cohesion and adhesion by std. methods. The dye addn. resulted in decreasing cohesion and adhesion to steel but also is increasing adhesion to the Si paper.
PL
Kleje samoprzylepne (PSA) mogą być zdefiniowane jako specjalna grupa klejów, które w postaci filmu klejowego posiadają właściwości samoprzylepne (w temperaturze pokojowej).Oprócz dobrej przyczepności powierzchniowej charakteryzują się dobrą stabilnością adhezji w dużej rozpiętości temperaturowej. Silikonowe kleje samoprzylepne (Si-PSA) charakteryzują się również obojętnością chemiczną i odpornością na warunki atmosferyczne. Są one szeroko stosowane do produkcji taśm i etykiet samoprzylepnych używanych gdy otoczenie lub powierzchnia podłoża przekracza możliwości przylepcowe typowych organicznych klejów samoprzylepnych. Właściwości samoprzylepnych klejów silikonowych (Si-PSA) sieciowanych termicznie organicznymi nadtlenkami (według mechanizmu rodnikowego) zależą od rodzaju oraz stężenia zastosowanych związków sieciujących. Zwiększenie stężenia nadtlenku benzoilu lub nadtlenku dichlorobenzoilu w układzie wpływało na ogół na znaczne zwiększenie kohezji, przy jednoczesnym zmniejszeniu adhezji badanego kleju.
EN
Pressure-sensitive adhesives (PSAs) can be defined as a special category of adhesives which in dry form are permanently tacky at room temperature. Pressure-sensitive adhesives require certain properties: good surface adhesion, good stability of adhesion characteristics is constant over a very wide temperature range. Siliconepressure-sensitive adhesives (Si-PSA) are characterized by chemical indifferenceandweather resistance. They are widely used in pressure-sensitive tapes and labels for applications when environmental conditions or the nature of substrate surfaces transcend the performance boundaries of common organic pressure-sensitive adhesives. The properties of thermally crosslinked silicone pressure-sensitive adhesives (Si-PSA) using organic peroxides (according to a radical mechanism) depend on the type and concentration of used crosslinker. Increasing the content of benzoyl peroxide or dichlorobenzoyl peroxide in the system affected (generally) increasing cohesion, while reducing the adhesion of the tested adhesives.
EN
Two-step method for comparative studies of water-soluble adhesives for labels was developed. Proposed method encompasses test and evaluation (five-point scale) of adhesion and peel-off time in water under certain conditions. The results of adhesion of acrylic water-soluble pressure-sensitive adhesives for various types of substrate (PET, glass, stainless steel) and peel-off time of selected model labels (paper, laminated paper, PET) are presented. The proposed method is quick and effective in determination the usefulness of adhesives for labels.
PL
Opracowano dwuetapową metodę porównawczą badania wodnorozpuszczalnych klejów do etykiet. Obejmuje ona badanie oraz ocenę (w skali pięciostopniowej) przyczepności (adhezji) oraz możliwości odrywania w określonych warunkach. W pracy przedstawiono wyniki adhezji kleju wodnorozpuszczalnego na bazie poliakrylanu do różnych typów podłoża (PET, szkło, stal) oraz czas odklejania wybranych modeli etykiet (papier, papier laminowany, PET). Zaproponowana metoda pozwala na szybkie i skutecznie określenie użyteczności kleju do etykiet dla danego typu podłoża.
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