Ntuj polymer - daim ntawv thov ntawm cov mis thiab

Feem ntau cov niaj hnub siv cov ntaub ntawv, pharmaceuticals, fabrics, tsev neeg cov khoom, ntim thiab consumable ntaub ntawv yog polymers. Yog ib pab pawg neeg ntawm tebchaw muaj tus yam ntxwv nta. Ib tug ntau ntawm lawv, tab sis nyob rau hauv cov kev phem ntawm no, cov xov tooj ntawm polymers tseem loj hlob tuaj. Tom qab tag nrho cov hluavtaws chemists sab txhua txhua xyoo ntau thiab ntau tshiab tshuaj. Nyob rau hauv cov ntaub ntawv no, tshwj xeeb tseem ceeb nyob rau hauv txhua lub sij hawm nws muaj ib tug tej yam ntuj tso polymer. Yuav ua li cas yog cov amazing molecules? Yuav ua li cas yog lawv tus yam ntxwv thiab dab tsi yog cov yam ntxwv? Cov lus teb rau cov lus nug no nyob rau hauv tsab xov xwm.

Polymers: general yam ntxwv

Los ntawm lub standpoint ntawm Science News for KIDS, lub polymer yog pom tias yuav ua tau ib tug qauv muaj ib tug loj molecular yuag los ntawm ib tug ob peb txhiab tsheej lab ntawm cov chav nyob. Txawm li cas los, dua li no feature, tseem muaj ib co nyob rau hauv uas lub substance yuav precisely dej num raws li ntuj thiab hluavtaws polymers. Lawv yog:

• lossi rov qab ua dua monomer units, uas yog kev cob cog rua los ntawm txoj kev sib txawv kev sib tshuam;
• degree polymerase (i.e., tus xov tooj ntawm monomers) yuav tsum yog heev siab heev, txwv tsis pub tus compound yuav xam tau tias ib tug oligomer;
• kev txiav txim ntsig txog orientation ntawm lub macromolecule;
• ib tug txheej ntawm ib qho tseem ceeb lub cev thiab tshuaj zog cim rau cov pab pawg neeg.

Nyob rau hauv dav dav, lub substance ntawm polymeric xwm distinguishable los ntawm lwm yam yooj yim heev. Ib tug muaj tsuas yog mus saib nyob rau ntawm nws mis kom paub tseeb. Ib tug raug piv txwv yog lub zoo-paub polyethylene, yog lug siv nyob rau hauv tsev neeg thiab kev lag luam. Nws yog ib yam khoom ntawm lub polymerization cov tshuaj tiv thaiv, uas nkag mus rau unsaturated hydrocarbon yog ethene los yog ethylene. Cov tshuaj tiv thaiv no feem ntau sau ib daim ntawv raws li nram no:

nCH ₂ = CH ₂ → (-CH-CH-) _n, nyob qhov twg n - yog cov neeg kawm ntawv ntawm polymerization ntawm molecules uas qhia raws li monomer units muaj nyob rau hauv nws cov muaj pes tsawg leeg.

Tsis tas li ntawd raws li ib qho piv txwv, ib tug tej yam ntuj tso polymer uas yog paub zoo tias, qhov no cov hmoov txhuv nplej. Ntxiv mus, nyob rau hauv pab pawg neeg no ntawm tebchaw yuav amylopectin, cellulose, nqaij qaib protein thiab ntau lwm yam tshuaj.

Cov tshuaj tiv thaiv, uas tau nyob rau hauv lub macromolecule peev xwm yuav tsim, yog ob hom:

• polymerization;
• polycondensation.

Qhov txawv yog tias nyob rau hauv lub thib ob cov ntaub ntawv, cov tshuaj tiv thaiv cov khoom uas tsis muaj molecular ceeb thawj. Tus qauv ntawm lub polymer yuav sib txawv, nyob ntawm seb lub atoms uas roos nws. Feem ntau muaj cov linear cov ntaub ntawv, tab sis muaj ib tug peb-dimensional mesh, heev.

Yog hais tias peb tham txog cov rog thiab kev sib tshuam uas tuav lub monomer units ua ke, nws yog tau hais tias ib tug ob peb yooj yim:

• Van ua dawb Waals rog;
• tshuaj tsevneeg (covalent, ionic);
• elektronostaticheskoe sis raug zoo.

Tag nrho cov polymers tsis tau ua ke mus rau hauv ib qeb vim hais tias lawv muaj ib tug kiag li cov xwm sib txawv, cov qauv ntawm cov tsim thiab ua txawv zog. Lawv lub zog kuj sib txawv. Yog li ntawd, muaj ib tug kev faib uas tso cai rau koj mus muab tag nrho cov mej zeej ntawm lub pab pawg neeg ntawm tshuaj mus rau hauv nyias pawg. Nws yog raws li yuav pw ob peb yam tshwm sim.

kev faib ntawm polymers

Yog hais tias peb coj lub hauv paus ntawm lub zoo pes tsawg leeg ntawm molecules, tag nrho cov ntawm cov tshuaj yuav tsum tau txiav txim nyob rau hauv peb pab pawg.

1. Lub organics - cov uas muaj cov pa roj carbon, hydrogen, sulfur, oxygen, phosphorus, nitrogen. Uas yog, cov neeg hais uas yog biogenic. Piv txwv yog hnyav polyethylene, polyvinyl tshuaj dawb, polypropylene, rayon, nylon, tej yam ntuj tso polymer - protein, nucleic acid thiab thiaj li nyob.
2. Elementorganic - xws li ib tug muaj pes tsawg leeg uas muaj xws li ib co extraneous inorganic thiab biogenic caij. Feem ntau cov feem ntau nws yog pob zeb ntais, txhuas los yog titanium. Piv txwv li macromolecules: organic iav, steklopolimery, puas cov ntaub ntawv.
3. Inorganic - dag ntawm lub hauv paus ntawm saw silicon atoms es tsis txhob ntawm carbon. Cov radicals kuj yog ib feem ntawm lub sab ceg. Lawv qhib raws li nyuam qhuav ua rau hauv nruab nrab ntawm lub XX caug xyoo. Siv nyob rau hauv cov tshuaj, kev tsim kho, engineering thiab lwm yam lag luam. Piv txwv ntawm silicone, cinnabar.

Yog hais tias koj tau faib cov polymers nyob hauv keeb kwm, nws yog ua tau kom paub tias peb ntawm lawv cov pab pawg neeg.

1. Ntuj polymers uas nws siv yog dav nqa tawm nrog cov laus. Cov no yog cov macromolecules rau creation ntawm uas tus txiv neej tsis ua tej yam kev rau siab. Lawv yog cov khoom ntawm qhov xwm ntawm tus tshua. Piv txwv: Txhob lo lo ntxhuav, wool, protein, nucleic acid, starch, cellulose, tawv, paj rwb thiab lwm tus neeg.
2. Dag. Cov no yog cov macromolecules uas yog tsim los ntawm tus txiv neej, tab sis nyob rau hauv lub hauv paus ntawm tej yam ntuj tso analogues. Uas yog cia li txhim kho thiab hloov cov khoom ntawm ib tug uas twb muaj lawm ntuj polymer. Piv txwv: hluavtaws roj hmab, roj hmab.
3. Khoom cua - cov polymers, lub creation ntawm uas tsuas yog tus neeg muab kev koom tes. Ntuj analogues rau lawv. Zaum tsim txoj kev synthesizing cov ntaub ntawv tshiab uas yog cov sib txawv mus txhim kho kev ua tau zoo. Yog li yog yug los rau hauv lub hluavtaws polymeric tebchaw ntawm tag nrho cov hom. Piv txwv: polyethylene, polypropylene, rayon, acetate fiber thiab cov zoo li.

Yog lwm feature, uas yog lub hauv paus ntawm kev sib cais ntawm cov tshuaj nyob rau hauv cov pab pawg neeg. Qhov no reactivity thiab thermal kuj. Faib ob pawg no parameter:

• thermoplastic;
• thermosets.

Qhov tseem ancient, ib qho tseem ceeb thiab tshwj xeeb tshaj yog tseem ceeb cov tseem yog ib tug natural polymer. Nws cov khoom yog cov cim. Yog li ntawd, peb tom ntej no saib nws yog ib qhov qeb ntawm macromolecules.

Uas tshuaj yog ib yam polymer?

Yuav kom teb tau lo lus nug no, peb saib ib ncig ntawm koj. Uas nyob ib ncig peb? Nyob kab mob nyob ib ncig ntawm peb cov uas noj, ua pa, muaj me tub, tawg thiab tsim txiv hmab txiv ntoo thiab noob. Thiab lawv yog cov los ntawm ib tug molecular taw tes ntawm view? Nws tebchaw xws li:

• proteins;
• nucleic acids;
• polysaccharides.

Yog li ntawd, lub ntuj polymer yog, txhua lub saum toj no tebchaw. Yog li, nws zoo nkaus li uas lub neej nyob ib ncig ntawm peb, muaj tsuas yog ua tsaug rau lub xub ntiag ntawm cov molecules. Txij ancient sij hawm, cov neeg siv av nplaum, hmoov sib tov thiab cov kev daws rau strengthening thiab tsev lub tsev, woven xov, wool, siv rau kev tsim paj rwb khaub ncaws, txhob lo lo ntxhuav, wool thiab daim tawv nqaij ntawm cov tsiaj. Ntuj organic polymers nrog tus txiv neej nyob txhua theem ntawm nws tsim thiab kev loj hlob, thiab nyob rau hauv ntau txoj kev uas tau pab nws ua mus cuag cov kev tshwm sim hais tias peb muaj niaj hnub no.

Qhov xwm heev ntawm muab tag nrho mus rau lub neej ntawm cov neeg yog li xis li sai tau. Thaum lub sij hawm, cov roj hmab twb tshwm sim, nws clarified nws zoo kawg li zog. Tus txiv neej tau kawm siv cov khoom noj kom starch, nyob rau hauv cov kev - cellulose. Ntuj polymer thiab yog ib tug camphor, uas yog tseem paub txij ancient sij hawm. Resins, cov nqaijrog, nucleic acids - yog tag nrho cov piv txwv ntawm lub tebchaw nyob rau hauv kev saib xyuas.

Tus qauv ntawm tej yam ntuj tso polymers

Tsis tag nrho cov neeg ntawm no hauv chav kawm ntawv ntawm tebchaw muaj tib lub qauv. Yog li, yam thiab hluavtaws polymers tej zaum yuav txawv muaj nuj nqis. Lawv molecules yog taw qhia kom paub li ntawd hais tias cov feem ntau muaj txiaj ntsim yooj yim thiab nyob ua ib ke nyob rau hauv cov nqe lus ntawm lub zog. Txawm li cas los, muaj ntau yam tej hom yuav tau swell thiab lawv cov qauv nyob rau hauv tus txheej txheem ntawm kev hloov. Muaj ntau ntau feem ntau variants ntawm lub saw qauv:

• linear;
• branched;
• stellate;
• tiaj;
• ntxaij;
• daim kab xev;
• zuag.

Dag thiab hluavtaws macromolecules cov neeg sawv cev muaj ib tug heev loj loj, ib tug loj loj tus naj npawb ntawm atoms. Lawv yog tsim nrog lawv qhov kev kawm lub zog. Yog li ntawd, tus qauv ntawm lawv Ameslikas npaj rau cov txiv neej. Ntuj polymers yog feem ntau kuj yog linear los yog mesh rau cov qauv.

Piv txwv ntawm tej yam ntuj tso macromolecules

Ntuj thiab hluavtaws polymers yog heev ze rau txhua lwm yam. Tom qab thawj ua lub hauv paus rau ib tug thib ob. Piv txwv li transformations ntau ntau. Ntawm no yog ib co ntawm lawv.

1. Pa yas ntais dawb - qhov no yog ib yam khoom muab los ntawm kev kho mob ntawm cellulose nrog nitric acid nrog rau qhov sib ntxiv ntawm tej yam ntuj tso camphor. Lub polymerization cov tshuaj tiv thaiv tau nyob rau hauv hardening ntawm lub polymer tau thiab hloov dua siab tshiab rau lub Desired khoom. Ib tug plasticizer - camphor, ua rau nws muaj peev xwm sawv ntawm softening thaum rhuab thiab hloov lawv zoo lawm.
2. Acetate txhob lo lo ntxhuav, cuprammonium fiber, viscose - yog tag nrho cov piv txwv ntawm cov yarns, fibers, uas yog tau nyob rau hauv lub hauv paus ntawm cellulose. Fabrics ua los ntawm tej yam ntuj tso paj rwb thiab linen yog tsis raws li muaj zog, tsis ci ntsa iab, ib qho yooj yim mus crease. Tab sis dag analogues ntawm cov raug deprived, uas ua rau lawv siv yog txaus nyiam heev.
3. Dag pob zeb, tsev ntaub ntawv, mixtures, tawv - yog tseem piv txwv ntawm polymers derived ntawm tej yam ntuj tso cov ntaub ntawv.

Ib tug yeeb tshuaj uas yog ib tug natural polymer, thiab tej zaum yuav siv nyob rau hauv qhov tseeb daim ntawv no. Tej piv txwv yog ib yam nkaus thiab ntau:

• rosin;
• Amber;
• cov hmoov txhuv nplej;
• amylopectin;
• cellulose;
• plaub;
• wool;
• paj rwb;
• txhob lo lo ntxhuav;
• MAAs;
• av nplaum;
• txiv qaub;
• proteins;
• nucleic acid thiab thiaj li nyob.

Nws yog ib qhov tseeb hais tias ua ntej peb ib tug hauv chav kawm ntawv ntawm tebchaw yog heev loj, suab tseem ceeb thiab muaj nuj nqis rau cov neeg. Tam sim no cia peb xav txog nyob rau hauv ntau yam ib co neeg sawv cev ntawm tej yam ntuj tso polymers, uas yog heev nrov rau lub caij.

Txhob lo lo ntxhuav thiab wool

Cov mis ntawm tej yam ntuj tso txhob lo lo ntxhuav polymer complex, vim hais tias nws tshuaj nyob tus yeees yog qhia los ntawm cov nram qab no Cheebtsam:

• fibroin;
• sericin;
• waxes;
• cov rog.

Nws tus kheej loj protein - fibroin, muaj ib tug tswv cuab ntawm ntau amino acid hom. Yog hais tias tam sim no nws mus rau lub polypeptide saw, nws yuav zoo li no: (-NH-CH ₂ -CO-NH-CH (CH ₃₎ -CO-NH-CH ₂ -CO-) _n. Thiab qhov no yog tsuas yog ib feem ntawm nws. Yog hais tias peb xav txog tej yam uas rau cov qauv los ntawm txoj kev van ua dawb Waals koom tsis tsawg sericin protein molecule, lawv yog sib tov ua ke nyob rau hauv ib conformation nrog ib tug ciab thiab nqaijrog, nws yog to taub yog vim li cas nws yog ib qhov nyuaj rau depict mis tej yam ntuj tso txhob lo lo ntxhuav.

Rau hnub tim, npaum li cas ntawm cov khoom no khoom siv rau Tuam Tshoj, rau nws qhib tej qhov chaw, muaj ib tug tej yam ntuj tso chaw rau lub ntsiab tsim - silkworm. Yav tas los, txij li thaum lub sij hawm ancient, ntuj txhob lo lo ntxhuav yog heev menyuam. Them taus cov khaub ncaws ntawm nws yuav tsuas noble, nplua nuj neeg. Niaj hnub no, muaj ntau yam ntawm cov yam ntxwv ntawm cov ntaub so ntswg yog neeg pluag. Piv txwv li, nws xav magnetized thiab crumpled, nyob rau hauv tas li ntawd, raug tus kab mob mus rau lub hnub poob nws ci thiab tarnish. Yog li ntawd, lawm nyob rau hauv siv hluavtaws derivatives thereof.

Ntaub plaub tsiaj - nws tseem yog ib tug natural polymer raws li ib tug khoom uas tseem ceeb heev functions ntawm daim tawv nqaij thiab sebaceous qog ntawm tsiaj. Raws li cov ntawm no lub protein cov khoom manufactured knitwear, uas, xws li txhob lo lo ntxhuav, yog ib tug tseem ceeb khoom.

cov hmoov txhuv nplej

Ntuj cov hmoov txhuv nplej yog ib yam khoom polymer tsob nroj lub neej. Lawv ua nws raws li ib tug tshwm sim ntawm tus txheej txheem ntawm photosynthesis thiab noog nyob rau hauv ntau qhov chaw ntawm lub cev. Nws tshuaj muaj pes tsawg leeg:

• amylopectin;
• amylose;
• alpha-qabzib.

Lub spatial qauv ntawm cov hmoov txhuv nplej yog heev branched, disordered. Vim muaj amylopectin, nws muaj peev xwm sawv ntawm o nyob rau hauv dej, ua ib tug thiaj li hu ua tshuaj txhuam. Qhov no colloidal tshuaj no yog siv nyob rau hauv lub kos duab thiab kev lag luam. Tshuaj, khoom noj khoom haus kev lag luam, zus tau tej cov wallpaper adhesives - nws tseem yog ib txoj kev siv cov tshuaj yeeb dej caw.

Ntawm cov nroj tsuag uas muaj lub siab tshaj plaws nqi ntawm cov hmoov txhuv nplej yuav qhia tau:

• pob kws;
• qos yaj ywm;
• mov;
• nplej;
• qos ntoo;
• oats;
• buckwheat;
• tsawb;
• sorghum.

Nyob rau lub hauv paus ntawm no biopolymer ci qhob cij, cov ua pasta, ua noj jelly, cereals thiab lwm yam khoom noj.

cellulose

Los ntawm lub standpoint ntawm Science News for KIDS, cov tshuaj yeeb dej caw - yog ib tug polymer uas nws muaj pes tsawg leeg yog qhia los ntawm cov mis (C ₆ H ₅ O _{5) n.} Monomer tsev saw yog ib tug beta-qabzib. Main qhov chaw ntawm cellulose cov ntsiab lus - yog lub cell phab ntsa ntawm cov nroj tsuag. Uas yog vim li cas cov ntoo - ib tug tseem ceeb qhov chaw ntawm no compound.

Cellulose - ib tug natural polymer uas muaj ib tug linear spatial qauv. Nws yog siv rau zus tau tej cov nram qab no ntawm cov khoom:

• sis plawv hniav thiab cov ntawv cov khoom;
• dag plaub;
• ntau hom ntawm tus txiv neej-ua fibers;
• paj rwb;
• yas;
• smokeless hmoov;
• films thiab thiaj li nyob.

Nws yog pom tseeb tias nws muaj tus nqi yog zoo kawg thiab. Yuav kom qhov no compound tej zaum yuav siv nyob rau hauv ntau lawm, nws yuav tsum tau pib mus rau extract los ntawm cov nroj tsuag. Qhov no yog ua los ntawm tas mus li ua noj ua haus ntawm cov ntoo nyob rau hauv tshwj xeeb pab kiag li lawm. Ntxiv ua, raws li tau zoo raws li reagents siv rau kev zom yog cov sib txawv. Muaj ob peb txoj kev:

• sulfite;
• nitrate;
• lub dej qab zib;
• sulfate.

Tom qab xws li kev kho mob, cov khoom tseem muaj impurities. Hauv plawv ntawm no lignin thiab hemicellulose. Yog xav tau tshem ntawm lawv, sis plawv hniav yog kho nrog chlorine los yog alkali.

Nyob rau hauv tib neeg, muaj yog tsis muaj tej lom catalysts uas muaj kev tswj los mus ua txhaum down no complex biopolymer. Txawm li cas los, ib co tsiaj (herbivores), nruj heev heev rau qhov no. Lawv plab khom tej yam kab mob uas ua rau nws rau lawv. Es tsis txhob muaj tus kab mob neeg zog rau lub neej thiab vaj tse. Qhov no daim ntawv ntawm symbiosis yog tsis tshua muaj pab rau ob tog.

roj hmab

Qhov no ntuj polymer muaj nqi economic nqi. Rau cov thawj lub sij hawm nws tau piav los ntawm Robert ua noj, uas nyob rau hauv ib qho ntawm nws mus nrhiav tau nws. Nws tshwm sim zoo li no. Tom qab tsaws nyob rau hauv cov kob qhov twg lub natives nyob tsis paub hais tias rau nws, nws twb loj hlob cus plaws greeted los ntawm lawv. Nws xim twb attracted los ntawm lub zos cov me nyuam, uas tau ua si ib qho txawv kev kawm. Qhov no kheej kheej lub cev yog repelled los ntawm hauv pem teb thiab dhia siab nyob rau hauv cov huab cua, ces xa rov qab.

Hais kom tus neeg hauv zos hais txog dab tsi yog tsim los ntawm no qho khoom ua si, Ua noj kawm tau hais tias qhov no solidifies lub kua txiv ntawm ib tsob ntoo - Hevea. Ntau tom qab, nws twb pom hais tias qhov no yog ib tug biopolymer roj hmab.

Cov tshuaj xwm ntawm lub compound paub - yog isoprene, tej yam ntuj tso undergone polymerization. Formula roj hmab (C ₅ H _{8) n.} Nws cov khoom, vim uas nws yog li ntawd mas ntshai, raws li nram no:

• elasticity;
• durability;
• hluav taws xob rwb thaiv tsev;
• watertight.

Txawm li cas los, muaj drawbacks. Nyob rau hauv txias tej yam kev mob nws yuav taus thiab nkig, thiab lub tshav kub - nplaum thiab khov. Uas yog vim li cas muaj ib tug yuav tsum tau rau lub synthesis ntawm analogues ntawm dag los yog hluavtaws los luj. Niaj hnub no rubbers yog lug siv nyob rau hauv engineering thiab muaj kev siv. Qhov tseem ceeb tshaj cov khoom raws li lawv:

• roj hmab;
• ebony.

amber

Nws yog ib tug natural polymer, txij thaum lub cob yog nyob rau hauv nws cov qauv, cov pob txha nws zoo lawm. Spatial qauv - cib amorphous polymer. Heev flammable, nws yuav zes cov nplaim taws ntawm ib tug match. Nws muaj lub luminescence zog. Qhov no yog ib qho tseem ceeb heev thiab tseem ceeb zoo, uas yog siv nyob rau hauv hniav nyiaj hniav kub. Ornaments rau lub hauv paus ntawm amber yog zoo nkauj heev thiab nyob rau hauv coob.

Nyob rau hauv tas li ntawd, lub biopolymer siv nyob rau hauv cov kev kho mob hom phiaj. Vim hais tias nws yog manufactured ntwav txhuam ntoo xim coatings mus rau ntau yam chaw.