LV14085B

LV14085B - All superelastic pressure sensor element

Info

Publication number: LV14085B
Application number: LVP-09-218A
Authority: LV
Inventors: Juris Zavickis; Maris Knite; Gatis Podins
Original assignee: Univ Rigas Tehniska
Priority date: 2009-12-10
Filing date: 2009-12-10
Publication date: 2010-04-20
Also published as: WO2011071355A1; LV14085A

Abstract

The invention is related to the field of material science and composite materials and can be utilized for elaboration and production of new perspective active elements. The production method of all superelastic pressure sensor element is proposed. The method includes the obtaining of the piezoresistive polyisoprene - nanostructured black composite (PINOK) - with reduced percolation threshold, using solution method and dispersing the electroconductive filler with ultrasound. The acquired sensor element originates with reduced concentration of conductive filler, the superelastic layer of PINOK with noticeably better electrical conductivity than sensitive element is used for electrodes and whole sensor element is enclosed into superelastic electro isolative protective casing by vulcanizing under pressur

Description

Izgudrojuma aprakstsDescription of the Invention

Izgudrojums attiecas uz materiālzinātnes un tehniskās fizikas jomām un var tikt izmantots jaunu perspektīvu aktīvo elementu izstrādē un izgatavošanā. Tehnikā plaši izplatīti dažādi sensorelementi, kas paredzēti spiediena konstatēšanai un/vai mērīšanai. Tie pamatā bāzēti uz pjezoelektriskiem kristāliem vai keramikām, tāpēc tie galvenokārt ir stingri noteiktas formas cieti elementi.The invention relates to the field of materials science and technical physics and can be used to develop and produce new perspective active elements. Various sensor elements for pressure detection and / or measurement are widely used in the art. They are mainly based on piezoelectric crystals or ceramics, so they are mainly solid elements of a certain shape.

Ir pierādīts [1], ka poliizoprēna gumijas un nanostrukturēta oglekļa PRINTEX ΧΕ2 kompozītam (PINOK) perkolācijas sliekšņa rajonā piemīt ievērojams pozitīvais pjezorezistīvais efekts (kompozīta elektriskā pretestība palielinās pieaugot mehāniskajam spiedienam) un to var izmantot kā ļoti jūtīgu spiediena detektoru/sensoru [2,3], Zinātniskajā literatūrā atrodami dati, ka superelastīga polimēra un nanostrukturēta oglekļa kompozītiem piemīt vājš negatīvais pjezorezistīvais efekts, un ir zināmi mēģinājumi tos pielietot mazāk jutīgu spiedes indikatoru izstrādē [4].It has been shown [1] that the polyisoprene rubber and nanostructured carbon PRINTEX ΧΕ2 composite (PINOK) in the percolation threshold region has a significant positive piezoresistive effect (the electrical resistance of the composite increases with increasing mechanical pressure) and can be used as a highly sensitive pressure detector [2,3]. ], There is evidence in the scientific literature that superelastic polymer and nanostructured carbon composites have a weak negative piezoresistive effect and attempts have been made to use them in the development of less sensitive pressure indicators [4].

Kā prototips izmantots līmēts superelastīgs daudzkomponentu pjezorezi stīvs sensorelements [2]. Kā galvenie tā trūkumi ir: pirmkārt - līmēta struktūra nenodrošina pietiekamu elementa strukturālu integritāti jeb monolītumu, t.i., laika gaitā elektrodi var atslāņoties no nanokompozīta; otrkārt - salīdzinoši liela pildvielas koncentrācija, pie kuras novērojama perkolācijas pāreja un attiecīgi arī pjezorezistīvais efekts.A glued superelastic multi-component piezorescence stiff sensor element is used as a prototype [2]. Its main drawbacks are: firstly, the bonded structure does not provide sufficient structural integrity or monolithicity of the element, i.e., the electrodes may become detached from the nanocomposite over time; secondly, a relatively high filler concentration at which percolation transition and consequently piezoresistive effect is observed.

Konkrētais izgudrojuma mērķis ir izveidot monolītu, viscaur superelastīgu pjezorezistīvu sensorelementu no PINOK. Izgudrojums piedāvā veidot sensorelementu vulkanizējot vienotā struktūrā daļēji vulkanizētas sagataves ar atšķirīgu elektrovadošās pildvielas koncentrāciju, turklāt pildvielu disperģē ar ultraskaņas maisīšanas metodi, kas samazina nepieciešamo pildvielas koncentrāciju, tādā veidā uzlabojot kompozītmateriāla superelastību. Kā pjezorezistīvo materiālu piedāvāts izmantot PINOK ar 5 masas daļām, kā kontaktu materiālu - PINOK ar 10 masas daļām un poliizoprēna gumiju bez elektrovadošas pildvielas kā elektroizolējošu apvalku. Paņēmiena realizācijas struktūra šķērsgriezumā attēlota 1. attēlā, kur: 1 - superelastīgs pjezorezistīvs PINOK; 2 superelastīgs elektrovadošs PINOK; 3 - misiņa stieple; 4 - lokani daudzdzīslu vara vadi ar izolāciju; 5 - superelastīgs elektroizolējošs apvalks. Komponentes 3 un 4 savā starpā savienotas lodējot.The specific object of the invention is to provide a monolithic, all-super-flexible piezo-resistive sensor element from PINOK. The invention proposes to form a sensor element by vulcanizing semi-vulcanized preforms with a different concentration of conductive filler into a single structure, further comprising dispersing the filler by an ultrasonic mixing method which reduces the required filler concentration, thereby improving the superelasticity of the composite material. It is proposed to use PINOK with 5 parts by weight as piezo-resisting material, and with PINOK with 10 parts by weight as contact material and polyisoprene rubber without conductive filler as an electrically insulating coating. The cross-sectional structure of the method is depicted in Figure 1, where: 1 - super-elastic piezo-resistive PINOK; 2 super elastic conductive PINOK; 3 - brass wire; 4 - insulated multi-core copper wires; 5 - Super elastic electrically insulating cover. Components 3 and 4 are interconnected by soldering.

PINOK iegūts šādi: vispirms ar aukstiem valčiem mehāniski samaisa dabīgo kaučuku ar nepieciešamajām vulkanizācijas piedevām, izņemot PRINTEX ΧΕ2. Pildvielu un matricas proporcijas attēlotas 1. tabulā, kur C vietā lietojama nepieciešamā PRINTEX ΧΕ2 koncentrācija, kas izteikta masas daļās un iegūta eksperimentāli, nosakot konkrētās pildvielas elektrovadāmības perkolācijas sliekšņa kritiskos parametrus. Iegūto jēlgumiju sasmalcina iespējami smalkos gabalos un šķīdina hloroformā attiecībā lOOg gumijas pret lOOOml hloroforma. Nepieciešamo daudzumu PRINTEX ΧΕ2 5min disperģē atsevišķi lOOOml tīra hloroforma, pielietojot īpatnējo ultraskaņas enerģiju lW/ml. Iegūto oglekļa dispersiju hlorofonnā pievieno jēlgumijas un hloroforma maisījumam un, intensīvi maisot, šķīdina un homogenizē vēl 24h. Pēc tam maisījumu atlej uz stikla pamatnes un ļauj hloroformam izgarot, iegūstot plēvi, ko homogenizē 8-10 reizes valcējot caur aukstiem valčiem ar iespējami mazāko spraugas atvērumu.PINOK is obtained as follows: first, cold rolls are mechanically mixed with natural rubber with the necessary vulcanisation additives, except for PRINTEX ΧΕ2. The proportions of filler and matrix are shown in Table 1, where instead of C the required concentration of PRINTEX ΧΕ2 expressed in parts by weight and obtained experimentally by determining the critical parameters of the percolation threshold of the specific conductivity of the filler is used. The resulting crude rubber is crushed into as small pieces as possible and dissolved in chloroform at 100 g of rubber per 100 ml of chloroform. The required amount of PRINTEX ΧΕ2 5min is dispersed separately in 10000ml of pure chloroform using the specific ultrasonic energy lW / ml. The resulting carbon dispersion in chloroform is added to the mixture of crude rubber and chloroform and, after vigorous stirring, is further dissolved and homogenized for 24 hours. The mixture is then poured onto a glass base and the chloroform is allowed to evaporate to form a film which is homogenized by rolling cold rolls 8 to 10 times with the smallest possible gap opening.

Tabula 1Table 1

PINOK ķīmiskais sastavsChemical composition of PINOK

Komponente In the component Saturs, m.d. Content, m.d. Dabīgais poliizoprēna kaučuks (Pl) Natural Polyisoprene Rubber (Pl) 100 100 Sērs (S) Sulfur (S) 3,5 3.5 Cikloheksil-benzotiazola-sulfenamīds (CBS) Cyclohexylbenzothiazole sulfenamide (CBS) 0,8 0.8 Cinka oksīds (ZnO) Zinc oxide (ZnO) 5 5 Stearinskābe Stearic acid 1 1 PRINTEX ΧΕ2 PRINTEX ΧΕ2 C C

Viscaur superelastīgu spiediena sensorelementu izgatavo, nepieciešamās sastāvdaļas nepilnīgi vulkanizējot nerūsējošā tērauda formās 100°C temperatūrā, 30atm spiedienā. Tad iegūtās sastāvdaļas savieno nepieciešamajā konfigurācijā un vulkanizē nerūsējošā tērauda formā 150°C temperatūrā. Nepilnīgās un galīgās vulkanizācijas ilgumi atkarīgi no izmantotā kaučuka tehnoloģiskajiem parametriem, kurus nosaka ar vulkanizācijas reometru. Atšķirībā no līmētā prototipa, iegūtajā sensorelementā komponentes savienotas vulkanizējot zem spiediena, kas nodrošina teicamu monolītumu, kā arī stabilu elektrisko kontaktu starp tā elektrovadošajām daļām.Throughout, the super-elastic pressure sensor is manufactured by incompletely vulcanizing the required components in stainless steel molds at 100 ° C and 30atm. The resulting components are then combined in the required configuration and vulcanized in a stainless steel form at 150 ° C. The times of incomplete and final vulcanization depend on the technological parameters of the rubber used, which are determined by the vulcanization rheometer. Unlike the glued-on prototype, the resulting sensor element is connected by vulcanization under pressure, which provides excellent monolithicity as well as stable electrical contact between its conductive parts.

Informācijas avoti:Sources of information:

1. M.Knite, V.Teteris, A.Kiploka, J.Kaupuzs, Polyisoprene-carbon black nanocomposites as tensile strain and pressure sensor materiāls, Sensor.Actuator., A: Physical, 110/1-3, 142 (2004).1. M.Knite, V.Teteris, A.Kiploka, J.Kaupuzs, Polyisoprene-carbon black nanocomposites as tensile strain and pressure sensor material, Sensor.Actuator., A: Physical, 110 / 1-3, 142 (2004). .

2. M.Knite, G.Podins, S.Zike, J.Zavickis, V.Tupureina, PROSPECTIVE ROBOTIC TACTILE SENSORS: Elastomer - carbon nanostructure composites as prospective materiāls for flexible robotie tactile sensors, Proc. of 5th International2. M.Knite, G.Podins, S.Zike, J.Zavicki, V.Tupureina, PROSPECTIVE ROBOTIC TACTILE SENSORS: Elastomer - carbon nanostructure composites as a prospective material for flexible robotie tactile sensors, Proc. of 5th International

Conference on informatics in Control, Automation and Roboties, Roboties andConference on informatics in Control, Automation and Robotics, Robotics and

Automation, VI, May 11-15, 2008, Funchal, Madeira - Portugal, 234-238 (prototips)Automation, VI, May 11-15, 2008, Funchal, Madeira - Portugal, 234-238 (prototype)

3. J.Zavickis, G.Malefan, M.Knite, V.Teteris, Polyisoprene-nanostructured carbon black functional composite for pressure sensors, proceedings of scientific conference of young scientists on energy issues (CYSENI) 2008, Kaunas, Lithuania, May 28-29, 2009,3. J.Zavicki, G.Malefan, M.Knite, V.Teteris, Polyisoprene-Nanostructured Carbon Black Functional Composite for Pressure Sensors, Proceedings of the Young Scientists on Energy Issues (CYSENI) 2008, Kaunas, Lithuania, May 28 -29, 2009,

ISSN 1822-7554 (6 pages)ISSN 1822-7554 (6 pages)

4. A.E.Job, F.A.Oliveira, N.Alves, J.A.Giacometti, L.H.C.Mattoso, Conductive composites of natūrai rubber and carbon black for pressure sensors, Synth.Met., 135-136, (2003).4. A.E.Job, F.A.Oliveira, N.Alves, J.A.Giacometti, L.H.C.Mattoso, Conductive Composites of Naturally Rubber and Carbon Black for Pressure Sensors, Synth.Met., 135-136, (2003).

PretenzijasClaims

Claims

1. Viscaur superelastīgs spiediena sensorelements, kas satur pjezorezistīvu poliizoprēna /nanostrukturēta oglekļa kompozīta (PINOK)/ slāni, PĪNOK elektrodus un izolējošus slāņus no poliizoprēna gumijas, atšķiras ar to, ka elektrodi izveidoti kā superelastīgi slāņi, bet sensorelementa sastāvdaļas izgatavotas katra atsevišķi, nepilnīgi vulkanizējot, un pēc tam savienotas vulkanizējot zem spiediena pie optimālas temperatūras.1. A super-elastic pressure transducer having a piezoresistive polyisoprene / nanostructured carbon composite (PINOK) / layer, a PIPE electrode, and a polyisoprene rubber insulating layer, characterized in that the electrodes are made of super-elastic layers and the components of the sensor element are individually incomplete. , and then bonded by vulcanization under pressure at optimum temperature.

2. Sensorelementa saskaņā ar 1. punktu izgatavošanas paņēmiens, kas raksturīgs ar to, ka nanostrukturēta oglekļa (NO) koncentrāciju pjezorezistīvajā slānī samazina, šķīdinot jēlgumiju hloroformā un disperģējot NO hloroformā ar ultraskaņu un iegūto šķīdumu un dispersiju mehāniski samaisot.2. A process for the manufacture of a sensor element according to claim 1, characterized in that the concentration of nanostructured carbon (NO) in the piezoresistive layer is reduced by dissolving the crude rubber in chloroform and dispersing the NO in chloroform by ultrasound and mixing the resulting solution and dispersion.