Knowledge

Adhesion

Source đź“ť

664: 678: 1405:(PDMS) stamp is made with small periodic post structures. The surface with the posts is placed face down on a smooth surface, such that the surface area in between each post is elevated above the smooth surface, like a roof supported by columns. Because of these attractive dispersive forces between the PDMS and the smooth substrate, the elevated surface – or “roof” – collapses down onto the substrate without any external force aside from the van der Waals attraction. Simple smooth 650: 669: 667: 666: 690: 1646:). For the most part, this is a phenomenon associated with diffusive bonding. The more time is given for a pair of surfaces exhibiting diffusive bonding to restructure, the more diffusion will occur, the stronger the adhesion will become. The aforementioned reaction of certain polymer-on-polymer surfaces to ultraviolet radiation and oxygen gas is an instance of hysteresis, but it will also happen over time without those factors. 1486: 668: 1118: 1294:, referred to as the origin dipole. Since any origin dipole is inherently oriented so as to be attracted to the adjacent dipoles it induces, while the other, more distant dipoles are not correlated with the original dipole by any phase relation (thus on average contributing nothing), there is a net attractive force in a bulk of such particles. When considering identical particles, this is called cohesive force. 1393: 1580: 782: 1106: 1495:
Diffusive bonding in polymer-on-polymer surfaces is the result of sections of polymer chains from one surface interdigitating with those of an adjacent surface. The freedom of movement of the polymers has a strong effect on their ability to interdigitate, and hence, on diffusive bonding. For example, cross-linked polymers are less capable of diffusion and
1703:
this applies very strongly to wetting liquids, but also to gas molecules that could adsorb onto the surface in question, thereby occupying potential adhesion sites. This last point is actually fairly intuitive: Leaving an adhesive exposed to air too long gets it dirty, and its adhesive strength will decrease. This is observed in the experiment: when
1627:). By intermixing periodic breaks into smooth, adhesive surfaces, the interface acquires valuable crack-arresting properties. Because crack initiation requires much greater stress than does crack propagation, surfaces like these are much harder to separate, as a new crack has to be restarted every time the next individual microstructure is reached. 1287:, the negative second term describes an attractive force between neighboring oscillators. The same argument can also be extended to a large number of coupled oscillators, and thus skirts issues that would negate the large scale attractive effects of permanent dipoles cancelling through symmetry, in particular. 1196:. However, experimental data showed that many of the compounds observed to experience van der Waals forces had no multipoles at all. London suggested that momentary dipoles are induced purely by virtue of molecules being in proximity to one another. By solving the quantum mechanical system of two electrons as 1150:. The contact angle of the three-phase system is a function not only of dispersive adhesion (interaction between the molecules in the liquid and the molecules in the solid) but also cohesion (interaction between the liquid molecules themselves). Strong adhesion and weak cohesion results in a high degree of 1702:
This argument can be extended to the idea that when a surface is in a medium with which binding is favorable, it will be less likely to adhere to another surface, since the medium is taking up the potential sites on the surface that would otherwise be available to adhere to another surface. Naturally
1396:
The two stages of PDMS microstructure collapse due to van der Waals attractions. The PDMS stamp is indicated by the hatched region, and the substrate is indicated by the shaded region. A) The PDMS stamp is placed on a substrate with the "roof" elevated. B) Van der Waals attractions make roof collapse
1059:
of two separate surfaces form ionic, covalent, or hydrogen bonds. The engineering principle behind chemical adhesion in this sense is fairly straightforward: if surface molecules can bond, then the surfaces will be bonded together by a network of these bonds. It bears mentioning that these attractive
1591:
is perhaps the most crucial of these effects, and is often seen on adhesive tapes. Stringing occurs when a separation of two surfaces is beginning and molecules at the interface bridge out across the gap, rather than cracking like the interface itself. The most significant consequence of this effect
1690:
is high, then each species finds it favorable to cohere while in contact with a foreign species, rather than dissociate and mix with the other. If this is true, then it follows that when the interfacial tension is high, the force of adhesion is weak, since each species does not find it favorable to
1538:
The strength of the adhesion between two materials depends on which of the above mechanisms occur between the two materials, and the surface area over which the two materials contact. Materials that wet against each other tend to have a larger contact area than those that do not. Wetting depends on
1494:
Diffusive forces are somewhat like mechanical tethering at the molecular level. Diffusive bonding occurs when species from one surface penetrate into an adjacent surface while still being bound to the phase of their surface of origin. One instructive example is that of polymer-on-polymer surfaces.
1657:
is true, one can also find evidence of it by performing “stop-start” measurements. In these experiments, two surfaces slide against one another continuously and occasionally stopped for some measured amount of time. Results from experiments on polymer-on-polymer surfaces show that if the stopping
1570:
In concert with the primary surface forces described above, there are several circumstantial effects in play. While the forces themselves each contribute to the magnitude of the adhesion between the surfaces, the following play a crucial role in the overall strength and reliability of an adhesive
1489:
The interface is indicated by the dotted line. A) Non-crosslinked polymers are somewhat free to diffuse across the interface. One loop and two distal tails are seen diffusing. B) Crosslinked polymers not free enough to diffuse. C) "Scissed" polymers very free, with many tails extending across the
1610:
The interplay of molecular scale mechanisms and hierarchical surface structures is known to result in high levels of static friction and bonding between pairs of surfaces. Technologically advanced adhesive devices sometimes make use of microstructures on surfaces, such as tightly packed periodic
1529:
Once across the interface, the tails and loops form whatever bonds are favorable. In the case of polymer-on-polymer surfaces, this means more van der Waals forces. While these may be brittle, they are quite strong when a large network of these bonds is formed. The outermost layer of each surface
1297:
When discussing adhesion, this theory needs to be converted into terms relating to surfaces. If there is a net attractive energy of cohesion in a bulk of similar molecules, then cleaving this bulk to produce two surfaces will yield surfaces with a dispersive surface energy, since the form of the
1145:
allows for direct quantitative adhesion measurements. Generally, cases where the contact angle is low are considered of higher adhesion per unit area. This approach assumes that the lower contact angle corresponds to a higher surface energy. Theoretically, the more exact relation between contact
1601:
adhesive agent, and a crack does propagate, it happens by a gradual process called “fingering”, rather than a rapid, brittle fracture. Stringing can apply to both the diffusive bonding regime and the chemical bonding regime. The strings of molecules bridging across the gap would either be the
1425:
These forces also act over very small distances – 99% of the work necessary to break van der Waals bonds is done once surfaces are pulled more than a nanometer apart. As a result of this limited motion in both the van der Waals and ionic/covalent bonding situations, practical effectiveness of
1525:
irradiation in the presence of oxygen gas, which suggests that adhesive devices employing diffusive bonding actually benefit from prolonged exposure to heat/light and air. The longer such a device is exposed to these conditions, the more tails are scissed and branch out across the interface.
1433:
As an additional consequence, increasing surface area often does little to enhance the strength of the adhesion in this situation. This follows from the aforementioned crack failure – the stress at the interface is not uniformly distributed, but rather concentrated at the area of failure.
665: 1592:
is the restraint of the crack. By providing the otherwise brittle interfacial bonds with some flexibility, the molecules that are stringing across the gap can stop the crack from propagating. Another way to understand this phenomenon is by comparing it to the
1596:
at the point of failure mentioned earlier. Since the stress is now spread out over some area, the stress at any given point has less of a chance of overwhelming the total adhesive force between the surfaces. If failure does occur at an interface containing a
2164:
Vinod, Appu; Reddy Bhimavarapu, Yagna Valkya; Hananovitz, Mor; Stern, Yotam; Gulec, Semih; Jena, Akash Kumar; Yadav, Sakshi; Gutmark, E. J.; Patra, Prabir K.; Tadmor, Rafael (11 November 2022). "Mucus-Inspired Tribology, a Sticky Yet Flowing Hydrogel".
869:. Another way to view the surface energy is to relate it to the work required to cleave a bulk sample, creating two surfaces. If the new surfaces are identical, the surface energy Îł of each surface is equal to half the work of cleavage, W: Îł = (1/2)W 1658:
time is short enough, resumption of smooth sliding is easy. If, however, the stopping time exceeds some limit, there is an initial increase of resistance to motion, indicating that the stopping time was sufficient for the surfaces to restructure.
1638:, in this case, refers to the restructuring of the adhesive interface over some period of time, with the result being that the work needed to separate two surfaces is greater than the work that was gained by bringing them together (W > Îł 1310:, gold, various polymers and solid gelatin solutions do not stay apart when their separating becomes small enough – on the order of 1–10 nm. The equation describing these attractions was predicted in the 1930s by De Boer and Hamaker: 1561:
Another factor determining the strength of an adhesive contact is its shape. Adhesive contacts of complex shape begin to detach at the "edges" of the contact area. The process of destruction of adhesive contacts can be seen in the film.
1727:
Lateral adhesion is the adhesion associated with sliding one object on a substrate such as sliding a drop on a surface. When the two objects are solids, either with or without a liquid between them, the lateral adhesion is described as
1530:
plays a crucial role in the adhesive properties of such interfaces, as even a tiny amount of interdigitation – as little as one or two tails of 1.25 angstrom length – can increase the van der Waals bonds by an order of magnitude.
1064:. This means in general not only that surfaces with the potential for chemical bonding need to be brought very close together, but also that these bonds are fairly brittle, since the surfaces then need to be kept close together. 2115:
de la Madrid, Rafael; Garza, Fabian; Kirk, Justin; Luong, Huy; Snowden, Levi; Taylor, Jonathan; Vizena, Benjamin (19 February 2019). "Comparison of the Lateral Retention Forces on Sessile, Pendant, and Inverted Sessile Drops".
978:
and the events that happen at a given surface, but as discussed below, the theory of these variables also yields some interesting effects that concern the practicality of adhesive surfaces in relation to their surroundings.
1278: 1583:
Fingering process. The hatched area is the receiving substrate, the dotted strip is the tape, and the shaded area in between is the adhesive chemical layer. The arrow indicates the direction of propagation for the
987:
There is no single theory covering adhesion, and particular mechanisms are specific to particular material scenarios. Five mechanisms of adhesion have been proposed to explain why one material sticks to another:
1417:
and stickers that adhere to glass without using any chemical adhesives are fairly common as toys and decorations and useful as removable labels because they do not rapidly lose their adhesive properties, as do
1986:
Tadmor, Rafael; Bahadur, Prashant; Leh, Aisha; N'guessan, Hartmann; Jaini, Rajiv; Dang, Lan (21 December 2009). "Measurement of Lateral Adhesion Forces at the Interface between a Liquid Drop and a Substrate".
1094:, although in larger or more complex molecules, there may be multiple "poles" or regions of greater positive or negative charge. These positive and negative poles may be a permanent property of a molecule ( 1380: 1734:. However, the behavior of lateral adhesion between a drop and a surface is tribologically very different from friction between solids, and the naturally adhesive contact between a flat surface and a 927:. These two energy quantities refer to the energy that is needed to cleave one species into two pieces while it is contained in a medium of the other species. Likewise for a three species system: Îł 1200:
at some finite distance from one another, being displaced about their respective rest positions and interacting with each other's fields, London showed that the energy of this system is given by:
87: 1098:) or a transient effect which can occur in any molecule, as the random movement of electrons within the molecules may result in a temporary concentration of electrons in one region ( 1521:
tails. The heightened concentration of these chain ends gives rise to a heightened concentration of polymer tails extending across the interface. Scission is easily achieved by
1181: 2033:
Tadmor, Rafael; Das, Ratul; Gulec, Semih; Liu, Jie; E. N’guessan, Hartmann; Shah, Meet; S. Wasnik, Priyanka; Yadav, Sakshi B. (18 April 2017). "Solid–Liquid Work of Adhesion".
1739: 1142: 1470:
in each other. This would be particularly effective with polymer chains where one end of the molecule diffuses into the other material. It is also the mechanism involved in
1695:(relative to the solid), and thus one can extrapolate that cohesion increases in non-wetting liquids and decreases in wetting liquids. One example that verifies this is 1426:
adhesion due to either or both of these interactions leaves much to be desired. Once a crack is initiated, it propagates easily along the interface because of the
1602:
molecules that had earlier diffused across the interface or the viscoelastic adhesive, provided that there was a significant volume of it at the interface.
1086:: the attraction between two molecules, each of which has a region of slight positive and negative charge. In the simple case, such molecules are therefore 766: 1298:
energy remain the same. This theory provides a basis for the existence of van der Waals forces at the surface, which exist between any molecules having
1169: 1008:. Other interlocking phenomena are observed on different length scales. Sewing is an example of two materials forming a large scale mechanical bond, 967: 1847:
Vert, Michel; Doi, Yoshiharu; Hellwich, Karl-Heinz; Hess, Michael; Hodge, Philip; Kubisa, Przemyslaw; Rinaudo, Marguerite; Schué, François (2012).
1005: 1699:
rubber, which has a work of self-adhesion of 43.6 mJ/m in air, 74 mJ/m in water (a nonwetting liquid) and 6 mJ/m in methanol (a wetting liquid).
1159: 1056: 1848: 1206: 1137:
almost always refers to dispersive adhesion. In a typical solid-liquid-gas system (such as a drop of liquid on a solid surrounded by air) the
636: 1588: 1184:. London theorized that attractive forces between molecules that cannot be explained by ionic or covalent interaction can be caused by 1742:(CAB), which uses a combination of centrifugal and gravitational forces to decouple the normal and lateral forces in the problem. 1316: 1518: 1385:
where P is the force (negative for attraction), z is the separation distance, and A is a material-specific constant called the
2395:
N. Maeda; Chen, N; Tirrell, M; Israelachvili, JN (2002). "Adhesion and Friction Mechanisms of Polymer-on-Polymer Surfaces".
2513: 1482:
powders are pressed together and heated, atoms diffuse from one particle to the next. This joins the particles into one.
1024:
at the joint. The strongest joints are where atoms of the two materials share or swap electrons (known respectively as
629: 1510:), on the other hand are freer to wander into the adjacent phase by extending tails and loops across the interface. 1499:
because they are bonded together at many points of contact, and are not free to twist into the adjacent surface. Un
1666:
Some atmospheric effects on the functionality of adhesive devices can be characterized by following the theory of
1172:, because they do not require either surface to have any permanent polarity. They were described in the 1930s by 43: 2613: 1290:
The additive nature of the dispersion effect has another useful consequence. Consider a single such dispersive
602: 303: 140: 2608: 2526:
A. Majmuder; Ghatak, A.; Sharma, A. (2007). "Microfluidic Adhesion Induced by Subsurface Microstructures".
769:. In addition to the cumulative magnitudes of these intermolecular forces, there are also certain emergent 622: 343: 229: 1807: 1738:
makes the lateral adhesion in this case, an individual field. Lateral adhesion can be measured using the
298: 207: 90: 2603: 2201: 1856: 1691:
bond to the other. The interfacial tension of a liquid and a solid is directly related to the liquid's
2284: 1192:
could account for attraction between molecules having permanent multipole moments that participate in
757:
responsible for the function of various kinds of stickers and sticky tape fall into the categories of
677: 1193: 1158:
condition with low measured contact angles. Conversely, weak adhesion and strong cohesion results in
214: 20: 1881: 509: 504: 293: 286: 119: 2239: 2494: 1551: 1177: 572: 567: 236: 2071:
Sadullah, Muhammad Subkhi; Xu, Yinfeng; Arunachalam, Sankara; Mishra, Himanshu (11 March 2024).
746:
refers to the tendency of similar or identical particles and surfaces to cling to one another.)
1009: 124: 547: 165: 2073:"Predicting droplet detachment force: Young-Dupré Model Fails, Young-Laplace Model Prevails" 1113:, surface tension causes them to be nearly spherical, and adhesion keeps the drops in place. 2535: 2404: 2299: 2234:
Y. Y. Huang; Zhou, Weixing; Hsia, K. J.; Menard, Etienne; Park, Jang-Ung; Rogers, John A.;
2084: 1996: 1941: 1593: 1402: 1302:. These forces are easily observed through the spontaneous jumping of smooth surfaces into 1147: 877: 754: 743: 385: 202: 182: 170: 114: 1012:
forms one on a medium scale, and some textile adhesives (glue) form one at a small scale.
8: 1671: 1197: 1083: 1073: 762: 587: 435: 328: 34: 2539: 2408: 2303: 2282: 2088: 2000: 1945: 2559: 2428: 2369: 2342: 2323: 2125: 1965: 1873: 1782: 739: 607: 241: 197: 192: 2551: 2469: 2448:"Strength of adhesive contacts: Influence of contact geometry and material gradients" 2420: 2374: 2315: 2262: 2235: 2182: 2143: 2050: 2012: 1957: 1797: 1777: 1762: 1443: 1303: 1284: 1165: 1087: 1060:
ionic and covalent forces are effective over only very small distances – less than a
1021: 997: 770: 758: 682: 224: 175: 2563: 2432: 2327: 1877: 2543: 2459: 2412: 2364: 2354: 2307: 2254: 2174: 2135: 2092: 2042: 2008: 2004: 1969: 1949: 1865: 1849:"Terminology for biorelated polymers and applications (IUPAC Recommendations 2012)" 1812: 1767: 1757: 1696: 1555: 1463: 1386: 1049: 1025: 562: 537: 450: 425: 420: 375: 2311: 1953: 2139: 2046: 1827: 1817: 1792: 1496: 1130: 1001: 971: 552: 476: 440: 390: 321: 310: 255: 157: 2097: 2072: 1667: 1514: 1507: 1410: 1091: 975: 862: 858: 557: 415: 380: 281: 187: 2488: 2464: 2447: 2597: 2473: 1869: 1772: 1735: 1547: 1451: 1138: 1110: 1099: 1079: 1029: 963:
is the energy of cleaving species 1 from species 2 in a medium of species 3.
912: 597: 430: 2547: 2416: 1517:
is the cutting up of polymer chains, resulting in a higher concentration of
2555: 2424: 2378: 2319: 2266: 2178: 2147: 2054: 2016: 1961: 1802: 1598: 1543: 1185: 1173: 1155: 1095: 718:: In biology, adhesion reflects the behavior of cells shortly after contact 582: 577: 542: 274: 2359: 1649:
In addition to being able to observe hysteresis by determining if W > Îł
704:
Process of attachment of a substance to the surface of another substance.
1692: 1522: 1513:
Another circumstance under which diffusive bonding occurs is “scission”.
1500: 1419: 649: 592: 495: 2285:"Macroscopic Evidence of the Effect of Interfacial Slippage on Adhesion" 1273:{\displaystyle E=3h\nu -{\frac {3}{4}}{\frac {h\nu \alpha ^{2}}{R^{6}}}} 753:
that cause adhesion and cohesion can be divided into several types. The
1635: 1620: 1615:
technologies inspired by the adhesive abilities of the feet of various
1612: 785:
Diagram of various cases of cleavage, with each unique species labeled.
657: 514: 410: 2258: 2186: 710:: Adhesion requires energy that can come from chemical and/or physical 2163: 1616: 1471: 1466:. This may occur when the molecules of both materials are mobile and 1447: 1442:
Some conducting materials may pass electrons to form a difference in
1299: 1189: 1061: 712:
linkages, the latter being reversible when enough energy is applied.
486: 481: 315: 2130: 1752: 1730: 1503: 1122: 1045: 1037: 1033: 735: 726:: In surgery, adhesion is used when two tissues fuse unexpectedly. 689: 465: 350: 336: 1485: 2283:
Bi-min Zhang Newby, Manoj K. Chaudhury and Hugh R. Brown (1995).
1822: 1787: 1479: 1467: 1427: 1406: 1151: 866: 219: 2394: 1146:
angle and work of adhesion is more involved and is given by the
1117: 1392: 1291: 1162:
conditions with high measured contact angles and poor wetting.
1041: 360: 1413:– are commonly used for these dispersive adhesive properties. 1985: 1624: 1475: 1414: 750: 697: 264: 1579: 2224:
F. London, "The General Theory of Molecular Forces" (1936).
2070: 1704: 1558:
are difficult to bond without special surface preparation.
1375:{\displaystyle {\frac {P}{area}}=-{\frac {A}{24\pi z^{3}}}} 1307: 781: 2446:
Popov, Valentin L.; Pohrt, Roman; Li, Qiang (2017-09-01).
2114: 1105: 2233: 653: 400: 1932:
K. Kendall (1994). "Adhesion: Molecules and Mechanics".
2525: 1446:
at the joint. This results in a structure similar to a
904:
are the surface energies of the two new surfaces, and Îł
1319: 1209: 1141:
is used to evaluate adhesiveness indirectly, while a
46: 1846: 1401:The effect is also apparent in experiments where a 1168:forces are particularly useful for the function of 673:
Adhesion of a frog on a wet vertical glass surface.
2110: 2108: 1715:, is smaller than the cleavage energy in vacuum, W 1374: 1272: 865:that is required to build an area of a particular 81: 2032: 2595: 2486: 1036:atom in one molecule is attracted to an atom of 2105: 1903: 1901: 2588:Adhesion and Adhesives: Science and Technology 2340: 2066: 2064: 1176:, and have been observed by many researchers. 1004:of the surfaces and hold surfaces together by 2583:, Royal Society of Chemistry Paperbacks, 1997 1661: 911:This methodology can also be used to discuss 630: 2490:Science friction: Adhesion of complex shapes 2445: 2028: 2026: 1981: 1979: 1898: 966:A basic understanding of the terminology of 2159: 2157: 2061: 1911:(Academic Press, New York, 1985). chap. 15. 82:{\displaystyle J=-D{\frac {d\varphi }{dx}}} 1931: 637: 623: 2463: 2368: 2358: 2129: 2096: 2023: 1976: 1927: 1925: 1923: 1921: 1919: 1917: 1707:is cleaved in air, its cleavage energy, W 1462:Some materials may merge at the joint by 1048:in another molecule, a phenomenon called 2519: 2390: 2388: 2278: 2276: 2154: 1578: 1484: 1391: 1116: 1104: 780: 688: 676: 662: 648: 2516:Tribology International 2016, Volume 93 2341:von Fraunhofer, Anthony (21 Feb 2012). 1397:energetically favorable for PDMS stamp. 2596: 2218: 1914: 1422:that use adhesive chemical compounds. 1078:In dispersive adhesion, also known as 974:is very helpful for understanding the 2514:Static Friction at Fractal Interfaces 2385: 2273: 2227: 2202:"What is required for good adhesion?" 1542:Low surface energy materials such as 1539:the surface energy of the materials. 1082:, two materials are held together by 2240:"Stamp Collapse in Soft Lithography" 1722: 1283:While the first term is simply the 1125:flower which shows better adhesion. 13: 2573: 2347:International Journal of Dentistry 2199: 1605: 1055:Chemical adhesion occurs when the 14: 2625: 1909:Intermolecular and Surface Forces 1430:nature of the interfacial bonds. 915:that happens in another medium: Îł 876:If the surfaces are unequal, the 861:is conventionally defined as the 776: 1565: 1437: 1121:Water droplets are flatter on a 1032:). A weaker bond is formed if a 2507: 2497:from the original on 2021-12-21 2487:Friction Physics (2017-12-06), 2480: 2439: 2334: 2193: 2009:10.1103/PhysRevLett.103.266101 1840: 1109:Cohesion causes water to form 734:is the tendency of dissimilar 1: 2312:10.1126/science.269.5229.1407 2167:ACS Applied Polymer Materials 1954:10.1126/science.263.5154.1720 1834: 1630: 1454:force between the materials. 1182:statistical quantum mechanics 1067: 991: 982: 2140:10.1021/acs.langmuir.8b03780 2047:10.1021/acs.langmuir.6b04437 1740:centrifugal adhesion balance 1574: 1457: 1143:Centrifugal Adhesion Balance 996:Adhesive materials fill the 7: 1808:Pressure-sensitive adhesive 1745: 1533: 1015: 908:is the interfacial energy. 10: 2630: 2098:10.1038/s42005-024-01582-0 1857:Pure and Applied Chemistry 1662:Wettability and absorption 1450:and creates an attractive 1071: 742:to cling to one another. ( 685:is caused due to adhesion. 18: 2465:10.1007/s40544-017-0177-3 2206:blog.biolinscientific.com 1194:electrostatic interaction 1020:Two materials may form a 21:Adhesion (disambiguation) 2590:, Chapman and Hall, 1987 1870:10.1351/PAC-REC-10-12-04 1090:with respect to average 141:Clausius–Duhem (entropy) 91:Fick's laws of diffusion 2548:10.1126/science.1145839 2417:10.1126/science.1072378 2343:"Adhesion and Cohesion" 1989:Physical Review Letters 1552:polytetrafluoroethylene 1409:surfaces – without any 299:Navier–Stokes equations 237:Material failure theory 2179:10.1021/acsapm.2c01434 2077:Communications Physics 1585: 1491: 1398: 1376: 1274: 1126: 1114: 970:, surface energy, and 855: 728: 693: 686: 674: 660: 83: 2614:Intermolecular forces 1907:J. N. Israelachvili, 1719:, by a factor of 13. 1697:polydimethyl siloxane 1582: 1488: 1395: 1377: 1306:. Smooth surfaces of 1275: 1180:are a consequence of 1120: 1108: 784: 755:intermolecular forces 702: 692: 680: 672: 652: 294:Bernoulli's principle 287:Archimedes' principle 84: 1674:. It is known that Îł 1594:stress concentration 1403:polydimethylsiloxane 1317: 1207: 1198:harmonic oscillators 1148:Young-Dupre equation 1084:van der Waals forces 878:Young-DuprĂ© equation 656:drops adhering to a 386:Cohesion (chemistry) 208:Infinitesimal strain 44: 19:For other uses, see 2609:Chemical properties 2540:2007Sci...318..258M 2409:2002Sci...297..379M 2360:10.1155/2012/951324 2304:1995Sci...269.1407Z 2089:2024CmPhy...7...89S 2001:2009PhRvL.103z6101T 1946:1994Sci...263.1720K 1672:interfacial tension 1074:Dispersive adhesion 763:dispersive adhesion 304:Poiseuille equation 35:Continuum mechanics 29:Part of a series on 2236:Alleyne, Andrew G. 1783:Fracture mechanics 1586: 1492: 1399: 1372: 1270: 1188:within molecules. 1127: 1115: 856: 771:mechanical effects 767:diffusive adhesion 694: 687: 675: 661: 510:Magnetorheological 505:Electrorheological 242:Fracture mechanics 79: 16:Molecular property 2604:Materials science 2259:10.1021/la0502185 2200:LaurĂ©n, Susanna. 2173:(11): 8527–8535. 2041:(15): 3594–3600. 1778:Contact mechanics 1763:Bacterial adhesin 1611:posts. These are 1444:electrical charge 1370: 1339: 1285:zero-point energy 1268: 1236: 1178:Dispersive forces 1166:London dispersion 759:chemical adhesion 670: 647: 646: 522: 521: 456: 455: 225:Contact mechanics 148: 147: 77: 2621: 2581:Adhesion Science 2568: 2567: 2534:(5848): 258–61. 2523: 2517: 2511: 2505: 2504: 2503: 2502: 2484: 2478: 2477: 2467: 2443: 2437: 2436: 2403:(5580): 379–82. 2392: 2383: 2382: 2372: 2362: 2338: 2332: 2331: 2298:(5229): 1407–9. 2289: 2280: 2271: 2270: 2244: 2231: 2225: 2222: 2216: 2215: 2213: 2212: 2197: 2191: 2190: 2161: 2152: 2151: 2133: 2124:(7): 2871–2877. 2112: 2103: 2102: 2100: 2068: 2059: 2058: 2030: 2021: 2020: 1983: 1974: 1973: 1940:(5154): 1720–5. 1929: 1912: 1905: 1896: 1895: 1893: 1892: 1886: 1880:. Archived from 1853: 1844: 1768:Capillary action 1758:Adhesive bonding 1723:Lateral adhesion 1556:polyoxymethylene 1387:Hamaker constant 1381: 1379: 1378: 1373: 1371: 1369: 1368: 1367: 1348: 1340: 1338: 1321: 1279: 1277: 1276: 1271: 1269: 1267: 1266: 1257: 1256: 1255: 1239: 1237: 1229: 1170:adhesive devices 1050:hydrogen bonding 1026:covalent bonding 720:to the surface. 671: 639: 632: 625: 471: 470: 436:Gay-Lussac's law 426:Combined gas law 376:Capillary action 261: 260: 104: 103: 88: 86: 85: 80: 78: 76: 68: 60: 26: 25: 2629: 2628: 2624: 2623: 2622: 2620: 2619: 2618: 2594: 2593: 2576: 2574:Further reading 2571: 2524: 2520: 2512: 2508: 2500: 2498: 2485: 2481: 2444: 2440: 2393: 2386: 2339: 2335: 2287: 2281: 2274: 2253:(17): 8058–68. 2242: 2232: 2228: 2223: 2219: 2210: 2208: 2198: 2194: 2162: 2155: 2113: 2106: 2069: 2062: 2031: 2024: 1984: 1977: 1930: 1915: 1906: 1899: 1890: 1888: 1884: 1851: 1845: 1841: 1837: 1832: 1828:Cohesion number 1818:Synthetic setae 1793:Insect adhesion 1748: 1725: 1718: 1714: 1710: 1689: 1685: 1681: 1677: 1664: 1656: 1652: 1645: 1641: 1633: 1623:(most notably, 1608: 1606:Microstructures 1577: 1568: 1536: 1497:interdigitation 1460: 1440: 1411:microstructures 1363: 1359: 1352: 1347: 1325: 1320: 1318: 1315: 1314: 1262: 1258: 1251: 1247: 1240: 1238: 1228: 1208: 1205: 1204: 1131:surface science 1076: 1070: 1018: 994: 985: 972:surface tension 968:cleavage energy 962: 958: 954: 950: 946: 942: 938: 934: 930: 926: 922: 918: 907: 903: 899: 895: 891: 887: 883: 872: 853: 849: 845: 841: 837: 830: 829: 825: 821: 814: 813: 809: 805: 801: 794: 793: 786: 779: 729: 719: 711: 701: 663: 643: 614: 613: 612: 532: 524: 523: 477:Viscoelasticity 468: 458: 457: 445: 395: 391:Surface tension 355: 258: 256:Fluid mechanics 248: 247: 246: 160: 158:Solid mechanics 150: 149: 101: 93: 69: 61: 59: 45: 42: 41: 24: 17: 12: 11: 5: 2627: 2617: 2616: 2611: 2606: 2592: 2591: 2586:A.J. Kinloch, 2584: 2575: 2572: 2570: 2569: 2518: 2506: 2479: 2458:(3): 308–325. 2438: 2384: 2333: 2272: 2226: 2217: 2192: 2153: 2104: 2060: 2022: 1995:(26): 266101. 1975: 1913: 1897: 1864:(2): 377–410. 1838: 1836: 1833: 1831: 1830: 1825: 1820: 1815: 1810: 1805: 1800: 1795: 1790: 1785: 1780: 1775: 1770: 1765: 1760: 1755: 1749: 1747: 1744: 1724: 1721: 1716: 1712: 1708: 1687: 1683: 1679: 1675: 1668:surface energy 1663: 1660: 1654: 1650: 1643: 1639: 1632: 1629: 1607: 1604: 1576: 1573: 1567: 1564: 1535: 1532: 1515:Chain scission 1508:thermoplastics 1459: 1456: 1439: 1436: 1383: 1382: 1366: 1362: 1358: 1355: 1351: 1346: 1343: 1337: 1334: 1331: 1328: 1324: 1281: 1280: 1265: 1261: 1254: 1250: 1246: 1243: 1235: 1232: 1227: 1224: 1221: 1218: 1215: 1212: 1092:charge density 1072:Main article: 1069: 1066: 1017: 1014: 993: 990: 984: 981: 976:physical state 960: 956: 952: 948: 944: 940: 936: 932: 928: 924: 920: 916: 905: 901: 897: 893: 889: 885: 881: 870: 859:Surface energy 851: 847: 843: 839: 835: 827: 823: 819: 811: 807: 803: 799: 791: 778: 777:Surface energy 775: 696: 695: 645: 644: 642: 641: 634: 627: 619: 616: 615: 611: 610: 605: 600: 595: 590: 585: 580: 575: 570: 565: 560: 555: 550: 545: 540: 534: 533: 530: 529: 526: 525: 520: 519: 518: 517: 512: 507: 499: 498: 492: 491: 490: 489: 484: 479: 469: 464: 463: 460: 459: 454: 453: 447: 446: 444: 443: 438: 433: 428: 423: 418: 413: 407: 404: 403: 397: 396: 394: 393: 388: 383: 381:Chromatography 378: 373: 367: 364: 363: 357: 356: 354: 353: 334: 333: 332: 313: 301: 296: 284: 271: 268: 267: 259: 254: 253: 250: 249: 245: 244: 239: 234: 233: 232: 222: 217: 212: 211: 210: 205: 195: 190: 185: 180: 179: 178: 168: 162: 161: 156: 155: 152: 151: 146: 145: 144: 143: 135: 134: 130: 129: 128: 127: 122: 117: 109: 108: 102: 99: 98: 95: 94: 89: 75: 72: 67: 64: 58: 55: 52: 49: 38: 37: 31: 30: 15: 9: 6: 4: 3: 2: 2626: 2615: 2612: 2610: 2607: 2605: 2602: 2601: 2599: 2589: 2585: 2582: 2578: 2577: 2565: 2561: 2557: 2553: 2549: 2545: 2541: 2537: 2533: 2529: 2522: 2515: 2510: 2496: 2492: 2491: 2483: 2475: 2471: 2466: 2461: 2457: 2453: 2449: 2442: 2434: 2430: 2426: 2422: 2418: 2414: 2410: 2406: 2402: 2398: 2391: 2389: 2380: 2376: 2371: 2366: 2361: 2356: 2352: 2348: 2344: 2337: 2329: 2325: 2321: 2317: 2313: 2309: 2305: 2301: 2297: 2293: 2286: 2279: 2277: 2268: 2264: 2260: 2256: 2252: 2248: 2241: 2237: 2230: 2221: 2207: 2203: 2196: 2188: 2184: 2180: 2176: 2172: 2168: 2160: 2158: 2149: 2145: 2141: 2137: 2132: 2127: 2123: 2119: 2111: 2109: 2099: 2094: 2090: 2086: 2082: 2078: 2074: 2067: 2065: 2056: 2052: 2048: 2044: 2040: 2036: 2029: 2027: 2018: 2014: 2010: 2006: 2002: 1998: 1994: 1990: 1982: 1980: 1971: 1967: 1963: 1959: 1955: 1951: 1947: 1943: 1939: 1935: 1928: 1926: 1924: 1922: 1920: 1918: 1910: 1904: 1902: 1887:on 2015-03-19 1883: 1879: 1875: 1871: 1867: 1863: 1859: 1858: 1850: 1843: 1839: 1829: 1826: 1824: 1821: 1819: 1816: 1814: 1813:Rail adhesion 1811: 1809: 1806: 1804: 1801: 1799: 1796: 1794: 1791: 1789: 1786: 1784: 1781: 1779: 1776: 1774: 1773:Cell adhesion 1771: 1769: 1766: 1764: 1761: 1759: 1756: 1754: 1751: 1750: 1743: 1741: 1737: 1733: 1732: 1720: 1717:mica/vac/mica 1713:mica/air/mica 1706: 1700: 1698: 1694: 1673: 1669: 1659: 1647: 1637: 1628: 1626: 1622: 1618: 1614: 1603: 1600: 1595: 1590: 1581: 1572: 1566:Other effects 1563: 1559: 1557: 1553: 1549: 1548:polypropylene 1545: 1540: 1531: 1527: 1524: 1520: 1516: 1511: 1509: 1505: 1502: 1498: 1487: 1483: 1481: 1477: 1473: 1469: 1465: 1455: 1453: 1452:electrostatic 1449: 1445: 1438:Electrostatic 1435: 1431: 1429: 1423: 1421: 1416: 1412: 1408: 1404: 1394: 1390: 1388: 1364: 1360: 1356: 1353: 1349: 1344: 1341: 1335: 1332: 1329: 1326: 1322: 1313: 1312: 1311: 1309: 1305: 1301: 1295: 1293: 1288: 1286: 1263: 1259: 1252: 1248: 1244: 1241: 1233: 1230: 1225: 1222: 1219: 1216: 1213: 1210: 1203: 1202: 1201: 1199: 1195: 1191: 1187: 1186:polar moments 1183: 1179: 1175: 1171: 1167: 1163: 1161: 1157: 1153: 1149: 1144: 1140: 1139:contact angle 1136: 1132: 1124: 1119: 1112: 1107: 1103: 1101: 1100:London forces 1097: 1096:Keesom forces 1093: 1089: 1085: 1081: 1080:physisorption 1075: 1065: 1063: 1058: 1057:surface atoms 1053: 1051: 1047: 1043: 1039: 1035: 1031: 1030:ionic bonding 1027: 1023: 1013: 1011: 1007: 1003: 999: 989: 980: 977: 973: 969: 964: 914: 909: 879: 874: 868: 864: 860: 833: 817: 797: 789: 783: 774: 772: 768: 764: 760: 756: 752: 747: 745: 741: 737: 733: 727: 725: 721: 717: 713: 709: 705: 699: 691: 684: 679: 659: 655: 651: 640: 635: 633: 628: 626: 621: 620: 618: 617: 609: 606: 604: 601: 599: 596: 594: 591: 589: 586: 584: 581: 579: 576: 574: 571: 569: 566: 564: 561: 559: 556: 554: 551: 549: 546: 544: 541: 539: 536: 535: 528: 527: 516: 513: 511: 508: 506: 503: 502: 501: 500: 497: 494: 493: 488: 485: 483: 480: 478: 475: 474: 473: 472: 467: 462: 461: 452: 449: 448: 442: 439: 437: 434: 432: 429: 427: 424: 422: 421:Charles's law 419: 417: 414: 412: 409: 408: 406: 405: 402: 399: 398: 392: 389: 387: 384: 382: 379: 377: 374: 372: 369: 368: 366: 365: 362: 359: 358: 352: 349: 345: 342: 338: 335: 330: 329:non-Newtonian 327: 323: 319: 318: 317: 314: 312: 309: 305: 302: 300: 297: 295: 292: 288: 285: 283: 280: 276: 273: 272: 270: 269: 266: 263: 262: 257: 252: 251: 243: 240: 238: 235: 231: 228: 227: 226: 223: 221: 218: 216: 215:Compatibility 213: 209: 206: 204: 203:Finite strain 201: 200: 199: 196: 194: 191: 189: 186: 184: 181: 177: 174: 173: 172: 169: 167: 164: 163: 159: 154: 153: 142: 139: 138: 137: 136: 132: 131: 126: 123: 121: 118: 116: 113: 112: 111: 110: 107:Conservations 106: 105: 97: 96: 92: 73: 70: 65: 62: 56: 53: 50: 47: 40: 39: 36: 33: 32: 28: 27: 22: 2587: 2580: 2579:John Comyn, 2531: 2527: 2521: 2509: 2499:, retrieved 2489: 2482: 2455: 2451: 2441: 2400: 2396: 2350: 2346: 2336: 2295: 2291: 2250: 2246: 2229: 2220: 2209:. Retrieved 2205: 2195: 2170: 2166: 2121: 2117: 2080: 2076: 2038: 2034: 1992: 1988: 1937: 1933: 1908: 1889:. Retrieved 1882:the original 1861: 1855: 1842: 1803:Mucoadhesion 1729: 1726: 1701: 1665: 1648: 1634: 1609: 1599:viscoelastic 1587: 1569: 1560: 1544:polyethylene 1541: 1537: 1528: 1512: 1493: 1461: 1441: 1432: 1424: 1420:sticky tapes 1400: 1384: 1296: 1289: 1282: 1174:Fritz London 1164: 1134: 1128: 1077: 1054: 1019: 1006:interlocking 995: 986: 965: 910: 875: 857: 831: 815: 795: 790:: Îł = (1/2)W 787: 748: 731: 730: 723: 722: 715: 714: 707: 706: 703: 496:Smart fluids 441:Graham's law 370: 347: 340: 325: 311:Pascal's law 307: 290: 278: 133:Inequalities 1736:liquid drop 1693:wettability 1621:vertebrates 1523:ultraviolet 1501:crosslinked 1133:, the term 515:Ferrofluids 416:Boyle's law 188:Hooke's law 166:Deformation 2598:Categories 2501:2017-12-30 2353:: 951324. 2211:2019-12-31 2131:1902.06721 1891:2013-07-16 1835:References 1636:Hysteresis 1631:Hysteresis 1617:arthropods 1613:biomimetic 1490:interface. 1190:Multipoles 1068:Dispersive 992:Mechanical 983:Mechanisms 880:applies: W 700:definition 658:spider web 568:Gay-Lussac 531:Scientists 431:Fick's law 411:Atmosphere 230:frictional 183:Plasticity 171:Elasticity 2474:2223-7690 2083:(1): 89. 1589:Stringing 1584:fracture. 1575:Stringing 1472:sintering 1464:diffusion 1458:Diffusive 1448:capacitor 1357:π 1345:− 1300:electrons 1249:α 1245:ν 1226:− 1223:ν 1160:lyophobic 1156:lyophilic 1062:nanometer 959:, where W 896:, where Îł 736:particles 608:Truesdell 538:Bernoulli 487:Rheometer 482:Rheometry 322:Newtonian 316:Viscosity 66:φ 54:− 2564:19769678 2556:17932295 2495:archived 2452:Friction 2433:32153774 2425:12130780 2379:22505913 2328:29499327 2320:17731150 2267:16089420 2247:Langmuir 2238:(2005). 2148:30724570 2118:Langmuir 2055:28121158 2035:Langmuir 2017:20366322 1962:17795378 1878:98107080 1798:Meniscus 1753:Adhesive 1746:See also 1731:friction 1682:= (1/2)W 1678:= (1/2)W 1571:device. 1534:Strength 1504:polymers 1135:adhesion 1123:Hibiscus 1046:fluorine 1038:nitrogen 1034:hydrogen 1022:compound 1016:Chemical 923:= (1/2)W 919:= (1/2)W 913:cleavage 826:= (1/2)W 822:= (1/2)W 744:Cohesion 740:surfaces 732:Adhesion 683:meniscus 681:Concave 466:Rheology 371:Adhesion 351:Pressure 337:Buoyancy 282:Dynamics 120:Momentum 2536:Bibcode 2528:Science 2405:Bibcode 2397:Science 2370:3296218 2300:Bibcode 2292:Science 2187:1922923 2085:Bibcode 1997:Bibcode 1970:1525799 1942:Bibcode 1934:Science 1823:Wetting 1788:Galling 1480:ceramic 1474:. When 1468:soluble 1428:brittle 1407:polymer 1304:contact 1152:wetting 867:surface 553:Charles 361:Liquids 275:Statics 220:Bending 2562:  2554:  2472:  2431:  2423:  2377:  2367:  2326:  2318:  2265:  2185:  2146:  2053:  2015:  1968:  1960:  1876:  1686:. If Îł 1625:geckos 1519:distal 1415:Decals 1292:dipole 1042:oxygen 1010:velcro 765:, and 751:forces 724:Note 3 716:Note 2 708:Note 1 603:Stokes 598:Pascal 588:Navier 583:Newton 573:Graham 548:Cauchy 451:Plasma 346:  344:Mixing 339:  324:  306:  289:  277:  265:Fluids 198:Strain 193:Stress 176:linear 125:Energy 2560:S2CID 2429:S2CID 2324:S2CID 2288:(PDF) 2243:(PDF) 2126:arXiv 1966:S2CID 1885:(PDF) 1874:S2CID 1852:(PDF) 1476:metal 1111:drops 1088:polar 1044:, or 1002:pores 998:voids 900:and Îł 698:IUPAC 578:Hooke 558:Euler 543:Boyle 401:Gases 2552:PMID 2470:ISSN 2421:PMID 2375:PMID 2351:2012 2316:PMID 2263:PMID 2183:OSTI 2144:PMID 2051:PMID 2013:PMID 1958:PMID 1711:or W 1705:mica 1670:and 1619:and 1554:and 1308:mica 1154:, a 863:work 749:The 593:Noll 563:Fick 115:Mass 100:Laws 2544:doi 2532:318 2460:doi 2413:doi 2401:297 2365:PMC 2355:doi 2308:doi 2296:269 2255:doi 2175:doi 2136:doi 2093:doi 2043:doi 2005:doi 1993:103 1950:doi 1938:263 1866:doi 1709:121 1684:212 1680:121 1653:+ Îł 1642:+ Îł 1478:or 1129:In 1102:). 1028:or 1000:or 961:132 957:132 955:= W 951:– W 947:– W 943:+ W 939:= W 935:– Îł 931:+ Îł 925:212 921:121 892:– Îł 888:+ Îł 884:= Îł 852:132 850:= W 846:– W 842:– W 838:+ W 834:: W 828:212 824:121 818:: Îł 810:– Îł 806:+ Îł 802:= Îł 798:: W 738:or 654:Dew 2600:: 2558:. 2550:. 2542:. 2530:. 2493:, 2468:. 2454:. 2450:. 2427:. 2419:. 2411:. 2399:. 2387:^ 2373:. 2363:. 2349:. 2345:. 2322:. 2314:. 2306:. 2294:. 2290:. 2275:^ 2261:. 2251:21 2249:. 2245:. 2204:. 2181:. 2169:. 2156:^ 2142:. 2134:. 2122:35 2120:. 2107:^ 2091:. 2079:. 2075:. 2063:^ 2049:. 2039:33 2037:. 2025:^ 2011:. 2003:. 1991:. 1978:^ 1964:. 1956:. 1948:. 1936:. 1916:^ 1900:^ 1872:. 1862:84 1860:. 1854:. 1688:12 1676:12 1550:, 1546:, 1389:. 1354:24 1052:. 1040:, 953:23 949:13 945:33 941:12 937:12 933:23 929:13 917:12 906:12 894:12 882:12 873:. 871:11 848:23 844:13 840:33 836:12 820:12 812:12 800:12 792:11 773:. 761:, 2566:. 2546:: 2538:: 2476:. 2462:: 2456:5 2435:. 2415:: 2407:: 2381:. 2357:: 2330:. 2310:: 2302:: 2269:. 2257:: 2214:. 2189:. 2177:: 2171:4 2150:. 2138:: 2128:: 2101:. 2095:: 2087:: 2081:7 2057:. 2045:: 2019:. 2007:: 1999:: 1972:. 1952:: 1944:: 1894:. 1868:: 1655:2 1651:1 1644:2 1640:1 1506:( 1365:3 1361:z 1350:A 1342:= 1336:a 1333:e 1330:r 1327:a 1323:P 1264:6 1260:R 1253:2 1242:h 1234:4 1231:3 1220:h 1217:3 1214:= 1211:E 902:2 898:1 890:2 886:1 854:. 832:D 816:C 808:2 804:1 796:B 788:A 638:e 631:t 624:v 348:· 341:· 331:) 326:· 320:( 308:· 291:· 279:· 74:x 71:d 63:d 57:D 51:= 48:J 23:.

Index

Adhesion (disambiguation)
Continuum mechanics
Fick's laws of diffusion
Mass
Momentum
Energy
Clausius–Duhem (entropy)
Solid mechanics
Deformation
Elasticity
linear
Plasticity
Hooke's law
Stress
Strain
Finite strain
Infinitesimal strain
Compatibility
Bending
Contact mechanics
frictional
Material failure theory
Fracture mechanics
Fluid mechanics
Fluids
Statics
Dynamics
Archimedes' principle
Bernoulli's principle
Navier–Stokes equations

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.

↑