Odp\u011b\u0148ova\u010d funguje pouze tehdy, pokud ho kapalina zcela nep\u0159ijme. Zn\u00ed to nelogicky, dokud se nepod\u00edv\u00e1te na film s p\u011bnou m\u00edsto na hotovou plechovku. Tyto produkty posuzuji podle jedin\u00e9ho krit\u00e9ria: tenk\u00e9 st\u011bny mezi dv\u011bma bublinami. Pokud p\u0159\u00edsada z\u016fstane rozpu\u0161t\u011bn\u00e1 v hlavn\u00edm objemu kapaliny, k t\u00e9to st\u011bn\u011b se nikdy nedostane. Pokud je prudce odm\u00edtnuta, vytvo\u0159\u00ed se z n\u00ed kuli\u010dky a zanech\u00e1 kr\u00e1tery. U\u017eite\u010dn\u00e9 typy se nach\u00e1zej\u00ed v \u00fazk\u00e9m p\u00e1smu mezi t\u011bmito dv\u011bma ne\u00fasp\u011b\u0161n\u00fdmi p\u0159\u00edpady.<\/p>\n
P\u011bna vydr\u017e\u00ed, proto\u017ee se na rozhran\u00ed vzduch\u2013voda hromad\u00ed povrchov\u011b aktivn\u00ed l\u00e1tky a udr\u017euj\u00ed film pru\u017en\u00fd. Vzduch neust\u00e1le p\u0159iv\u00e1d\u00ed rozpra\u0161ovac\u00ed kotou\u010d, \u010derpadlo, st\u0159\u00edkac\u00ed pistole nebo provzdu\u0161\u0148ovac\u00ed n\u00e1dr\u017e. Kapka odp\u011b\u0148ova\u010de mus\u00ed proniknout do tohoto filmu, rozprost\u0159\u00edt se po n\u011bm a zanechat slab\u00fd m\u016fstek, aby kapalina odt\u00e9kala a bublina se zhroutila. Vniknut\u00ed a rozprost\u0159en\u00ed vy\u017eaduj\u00ed ni\u017e\u0161\u00ed povrchov\u00e9 nap\u011bt\u00ed ne\u017e m\u00e1 p\u011bniv\u00e1 kapalina a n\u00edzkou rozpustnost v n\u00ed. V tom spo\u010d\u00edv\u00e1 cel\u00e9 tajemstv\u00ed. Polydimethylsiloxan m\u00e1 povrchov\u00e9 nap\u011bt\u00ed v\u016f\u010di vod\u011b kolem 20 mN\/m, zat\u00edmco voda m\u00e1 72 mN\/m, tak\u017ee se rozprost\u00edr\u00e1 obt\u00ed\u017en\u011b. Hydrofobn\u00ed oxid k\u0159emi\u010dit\u00fd v mnoha emulz\u00edch pak p\u016fsob\u00ed jako \u0161pendl\u00edk a dokon\u010d\u00ed prasknut\u00ed bubliny. Odp\u011b\u0148ova\u010d na b\u00e1zi miner\u00e1ln\u00edho oleje s hydrofobn\u00edmi \u010d\u00e1sticemi vykon\u00e1v\u00e1 stejnou pr\u00e1ci, av\u0161ak pomaleji. Polyetherov\u00e9 typy \u010dasto reaguj\u00ed na teplotu: p\u0159i n\u00edzk\u00fdch teplot\u00e1ch p\u016fsob\u00ed m\u00e9n\u011b, ztr\u00e1cej\u00ed rozpustnost v bl\u00edzkosti bodu zakalen\u00ed a teprve pot\u00e9 obsad\u00ed rozhran\u00ed.<\/p>\n
Laboratorn\u00ed kel\u00edmky to zakr\u00fdvaj\u00ed. Test prot\u0159ep\u00e1n\u00edm odm\u011b\u0148uje rychl\u00e9 potla\u010den\u00ed p\u011bny. Cirkula\u010dn\u00ed potrub\u00ed odm\u011b\u0148uje kapku, kter\u00e1 p\u0159etrv\u00e1 i po p\u016fsoben\u00ed smykov\u00e9ho nam\u00e1h\u00e1n\u00ed, tepla a celodenn\u00edho \u010derp\u00e1n\u00ed. P\u0159\u00edli\u0161 velk\u00e9 mno\u017estv\u00ed emulg\u00e1toru zp\u016fsob\u00ed, \u017ee odp\u011b\u0148ova\u010d vypad\u00e1 ve slo\u017een\u00ed \u201chezky\u201d, ale na bubliny nem\u00e1 \u017e\u00e1dn\u00fd \u00fa\u010dinek. P\u0159\u00edli\u0161 m\u00e1lo emulg\u00e1toru nebo nespr\u00e1vn\u00fd silikon a na zaschl\u00e9m povlaku se objev\u00ed \u201eryb\u00ed o\u010di\u201c, mastn\u00fd z\u00e1kal nebo vrstva, kter\u00e1 se ned\u00e1 navlh\u010dit. S ob\u011bma vadami jsem se pot\u00fdkal ve stejn\u00e9m t\u00fddnu p\u0159i pou\u017eit\u00ed stejn\u00e9ho prysky\u0159i\u010dn\u00e9ho syst\u00e9mu. D\u00e1vka se t\u00e9m\u011b\u0159 nezm\u011bnila. Zm\u011bnila se v\u0161ak kompatibilita.<\/p>\n
Proto jsem rozd\u011blil p\u0159\u00edsady do n\u00e1t\u011brov\u00fdch hmot na vodn\u00ed b\u00e1zi. \u010c\u00e1st se p\u0159id\u00e1v\u00e1 do mlec\u00edho procesu, proto\u017ee ml\u00fdn vytv\u00e1\u0159\u00ed vzduch a z\u00e1rove\u0148 rozemele hrub\u00e9 kapi\u010dky na velikost, se kterou si film porad\u00ed. \u010c\u00e1st se p\u0159id\u00e1v\u00e1 do \u0159edic\u00edho procesu, aby zachytila mikrop\u011bnu, kter\u00e1 se objevuje a\u017e p\u0159i stoupaj\u00edc\u00ed viskozit\u011b. Jedna dodate\u010dn\u00e1 d\u00e1vka vypad\u00e1 na pap\u00ed\u0159e efektivn\u011b. Zanech\u00e1v\u00e1 v\u0161ak drobn\u00e9 bublinky uv\u011bzn\u011bn\u00e9 v tuhnouc\u00edm filmu. U procesn\u00ed vody plat\u00ed stejn\u00fd princip, jen s jin\u00fdmi jednotkami: stabiln\u00ed koncentrace v \u0159\u00e1du n\u011bkolika des\u00edtek ppm obvykle p\u0159ed\u010d\u00ed panick\u00e9 vypou\u0161t\u011bn\u00ed do p\u011bnic\u00ed n\u00e1dr\u017ee.<\/p>\n
Kdy\u017e po hodin\u011b cirkulace dojde ke ztr\u00e1t\u011b stability, nezvy\u0161uji hned d\u00e1vku p\u0159\u00edpravku. Zji\u0161\u0165uji, zda se hydrofobn\u00ed l\u00e1tka roz\u0161t\u011bpila do kompatibiln\u00ed podoby, zda pH rozlo\u017eilo emulzi, nebo zda byl dan\u00fd typ p\u0159\u00edpravku vyvinut pouze k odstran\u011bn\u00ed povrchov\u00e9 p\u011bny, nikoli mikrop\u011bny v hlavn\u00edm objemu. Zv\u00fd\u0161en\u00ed d\u00e1vky u typu p\u0159\u00edpravku, kter\u00fd se ji\u017e rozpustil, vede k vzniku povrchov\u00fdch vad a k tomu, \u017ee p\u011bna z\u016fstane zachov\u00e1na.<\/p>\n
Technick\u00e1 ot\u00e1zka tedy nezn\u00ed: \u201cKter\u00fd odp\u011b\u0148ova\u010d je nej\u00fa\u010dinn\u011bj\u0161\u00ed?\u201d Jde o to, zda se kapi\u010dka dok\u00e1\u017ee udr\u017eet v pon\u011bkud nevhodn\u00e9 poloze dostate\u010dn\u011b dlouho, aby mohla film st\u00e1le nach\u00e1zet. Toto \u010dasov\u00e9 okno je \u00fazk\u00e9. Pokud se netref\u00edte ani z jedn\u00e9 strany, n\u00e1dr\u017e vypad\u00e1 op\u011bt ru\u0161n\u011b, nebo se film jev\u00ed jako p\u0159eru\u0161en\u00fd.<\/p>","protected":false},"excerpt":{"rendered":"
How Antifoaming Agent Control Foam at the Interface An antifoaming agent only works if the liquid does not fully accept it. That sounds backwards until you watch a foam film instead of a finished can. I judge these products from one place: the thin wall between two bubbles. If the additive stays dissolved in the… Jak protip\u011bniv\u00e1 \u010dinidla potla\u010duj\u00ed p\u011bnu na rozhran\u00ed<\/span><\/a><\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"neve_meta_sidebar":"","neve_meta_container":"","neve_meta_enable_content_width":"off","neve_meta_content_width":70,"neve_meta_title_alignment":"","neve_meta_author_avatar":"","neve_post_elements_order":"","neve_meta_disable_header":"","neve_meta_disable_footer":"","neve_meta_disable_title":"","footnotes":""},"categories":[2],"tags":[],"class_list":["post-322","post","type-post","status-publish","format-standard","hentry","category-knowledge"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/antifoamingagent.net\/cs\/wp-json\/wp\/v2\/posts\/322","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/antifoamingagent.net\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/antifoamingagent.net\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/antifoamingagent.net\/cs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/antifoamingagent.net\/cs\/wp-json\/wp\/v2\/comments?post=322"}],"version-history":[{"count":1,"href":"https:\/\/antifoamingagent.net\/cs\/wp-json\/wp\/v2\/posts\/322\/revisions"}],"predecessor-version":[{"id":323,"href":"https:\/\/antifoamingagent.net\/cs\/wp-json\/wp\/v2\/posts\/322\/revisions\/323"}],"wp:attachment":[{"href":"https:\/\/antifoamingagent.net\/cs\/wp-json\/wp\/v2\/media?parent=322"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/antifoamingagent.net\/cs\/wp-json\/wp\/v2\/categories?post=322"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/antifoamingagent.net\/cs\/wp-json\/wp\/v2\/tags?post=322"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}