Natural polymer - formula thiab daim ntawv thov

2024 Tus sau: Angel Austin | [email protected]. Kawg hloov kho: 2023-12-17 05:28

Feem ntau ntawm cov khoom siv hauv tsev niaj hnub no, tshuaj, ntaub, khoom siv hauv tsev, ntim khoom thiab khoom siv yog polymers. Qhov no yog tag nrho pawg ntawm cov tebchaw uas muaj cov yam ntxwv sib txawv. Muaj ntau ntawm lawv, tab sis txawm tias qhov no, tus naj npawb ntawm cov polymers txuas ntxiv mus. Tom qab tag nrho, hluavtaws chemists txhua xyoo nrhiav tau ntau thiab ntau yam tshiab. Nyob rau tib lub sijhawm, nws yog lub ntuj polymer uas yog qhov tseem ceeb ntawm txhua lub sijhawm. Dab tsi yog qhov amazing molecules? Dab tsi yog lawv cov khoom thiab cov yam ntxwv yog dab tsi? Peb yuav teb cov lus nug no hauv chav kawm ntawm kab lus.

Polymers: general yam ntxwv

Los ntawm qhov pom ntawm chemistry, ib qho polymer raug suav tias yog ib qho molecule uas muaj qhov hnyav molecular: los ntawm ntau txhiab mus rau lab units. Txawm li cas los xij, ntxiv rau qhov tshwj xeeb no, muaj ntau yam ntxiv los ntawm cov tshuaj muaj peev xwm raug cais tawm raws li ntuj thiab hluavtaws polymers. Nov yog:

• tas mus li rov ua monomeric units uas txuas nrog los ntawm kev sib cuam tshuam;
• qib ntawm polymerase (piv txwv li tus naj npawb ntawm monomers) yuav tsum yog heevsiab, txwv tsis pub cov compound yuav raug suav hais tias yog oligomer;
• qee qhov kev taw qhia ntawm macromolecule;
• ib txheej ntawm cov khoom tseem ceeb ntawm lub cev thiab tshuaj lom neeg uas tshwj xeeb rau pawg no.

Feem ntau, cov khoom ntawm cov khoom siv polymeric yog qhov yooj yim kom paub qhov txawv ntawm lwm tus. Ib tug tsuas yog saib nws tus qauv kom nkag siab nws. Ib qho piv txwv zoo yog polyethylene paub zoo, siv dav hauv lub neej txhua hnub thiab kev lag luam. Nws yog cov khoom ntawm cov tshuaj tiv thaiv polymerization nyob rau hauv uas cov unsaturated hydrocarbon ethene los yog ethylene nkag. Cov tshuaj tiv thaiv hauv daim ntawv no yog sau raws li hauv qab no:

nCH₂=CH₂→(-CH-CH-) _{, qhov twg n yog qib ntawm polymerization ntawm molecules, qhia tias muaj pes tsawg monomeric units suav nrog hauv nws cov muaj pes tsawg leeg.}

Tsis tas li, ua piv txwv, ib tus tuaj yeem hais txog lub ntuj polymer, uas paub zoo rau txhua tus, nws yog cov hmoov txhuv nplej siab. Tsis tas li ntawd, amylopectin, cellulose, nqaij qaib protein thiab ntau lwm yam tshuaj muaj nyob rau hauv cov pab pawg neeg ntawm cov tebchaw.

Cov tshuaj tiv thaiv uas tuaj yeem tsim macromolecules yog ob hom:

• polymerization;
• polycondensation.

Qhov txawv yog qhov thib ob, cov khoom sib cuam tshuam yog qhov hnyav molecular. Cov qauv ntawm cov polymer tuaj yeem sib txawv, nws nyob ntawm cov atoms uas tsim nws. Cov ntaub ntawv linear feem ntau pom, tab sis kuj tseem muaj peb-dimensional meshes, uas nyuaj heev.

Yog tias peb tham txog lub zog thiab kev sib cuam tshuam uas tuav cov monomer units ua ke, ces peb tuaj yeem txheeb xyuas ob peb yam yooj yim:

• Van Der Waalszog;
• chemical bonds (covalent, ionic);
• electrostatic interaction.

Txhua cov polymers tsis tuaj yeem ua ke rau hauv ib pawg, vim lawv muaj qhov sib txawv kiag li, txoj kev tsim thiab ua haujlwm sib txawv. Lawv cov khoom kuj txawv. Yog li ntawd, muaj ib qho kev faib tawm uas tso cai rau koj faib tag nrho cov neeg sawv cev ntawm pab pawg ntawm cov khoom no rau hauv ntau pawg. Tej zaum nws yuav ua raws li ob peb lub cim.

YKev faib tawm ntawm cov polymers

Yog tias peb coj los ua qhov zoo ntawm cov molecules, ces tag nrho cov tshuaj uas tau txiav txim siab tuaj yeem muab faib ua peb pawg.

1. Organic - cov no yog cov atoms ntawm carbon, hydrogen, sulfur, oxygen, phosphorus, nitrogen. Ntawd yog, cov ntsiab lus uas yog biogenic. Muaj ntau yam piv txwv: polyethylene, polyvinyl chloride, polypropylene, viscose, nylon, ntuj polymer - protein, nucleic acids thiab lwm yam.
2. Elementalorganic - cov uas suav nrog qee cov khoom tsis muaj tshuaj lom thiab tsis-biogenic. Feem ntau nws yog silicon, aluminium lossis titanium. Piv txwv ntawm xws li macromolecules: organic iav, iav polymers, cov ntaub ntawv sib xyaw.
3. Inorganic - cov saw hlau yog nyob ntawm silicon atoms, tsis yog carbon. Radicals tuaj yeem yog ib feem ntawm sab ceg. Lawv tau pom tsis ntev los no, nyob rau hauv nruab nrab ntawm lub xyoo pua 20th. Siv hauv tshuaj, kev tsim kho, engineering thiab lwm yam lag luam. Piv txwv li: silicone, cinnabar.

Yog tias koj cais cov polymers los ntawm keeb kwm, koj tuaj yeem ua tauxaiv peb pawg ntawm lawv.

1. Natural polymers, kev siv uas tau siv dav txij li qub txeeg qub teg. Cov no yog cov macromolecules zoo li no, rau kev tsim uas ib tug neeg tsis tau siv zog. Lawv yog cov khoom ntawm cov tshuaj tiv thaiv ntawm qhov nws tus kheej. Piv txwv li: silk, wool, protein, nucleic acids, starch, cellulose, tawv, paj rwb, thiab lwm yam.
2. Artificial. Cov no yog cov macromolecules uas yog tsim los ntawm tib neeg, tab sis raws li natural analogues. Ntawd yog, cov khoom ntawm ib qho uas twb muaj lawm ntuj polymer tsuas yog txhim kho thiab hloov. Piv txwv li: roj hmab dag, roj hmab.
3. Synthetic - cov no yog cov polymers hauv kev tsim uas tsuas yog ib tus neeg koom. Tsis muaj cov analogues ntuj rau lawv. Cov kws tshawb fawb tab tom tsim cov txheej txheem rau kev sib txuas ntawm cov ntaub ntawv tshiab uas yuav muaj kev txhim kho cov yam ntxwv. Qhov no yog li cas hluavtaws polymer tebchaw ntawm ntau yam tau yug los. Piv txwv li: polyethylene, polypropylene, viscose, acetate fiber, thiab lwm yam.

Muaj ib qho ntxiv uas qhia txog kev faib cov tshuaj uas xav tau rau hauv pab pawg. Cov no yog reactivity thiab thermal stability. Muaj ob pawg rau qhov ntsuas no:

• thermoplastic;
• thermoset.

Qhov qub tshaj plaws, tseem ceeb thiab tshwj xeeb tshaj yog muaj txiaj ntsig tseem yog ntuj polymer. Nws cov khoom yog tshwj xeeb. Yog li ntawd, peb yuav xav txog qhov tshwj xeeb ntawm pawg macromolecules.

Cov tshuaj twg yog cov khoom siv ntuj tsim?

Tau teb lo lus nug no, cia peb xub saib ib ncig ntawm peb. Dab tsi nyob ib puag ncig peb?Cov kab mob nyob ib puag ncig peb uas pub, ua pa, tsim tawm, tawg thiab tsim cov txiv hmab txiv ntoo thiab noob. Thiab lawv sawv cev li cas los ntawm qhov kev xav ntawm molecular? Cov no yog kev sib txuas xws li:

• proteins;
• nucleic acids;

Ypolysaccharides.

Yog li, txhua qhov sib xyaw no yog cov khoom siv ntuj tsim. Yog li, nws hloov tawm tias lub neej nyob ib puag ncig peb tsuas yog tshwm sim vim muaj cov molecules. Txij li thaum ancient sij hawm, tib neeg tau siv av nplaum, tsev sib tov thiab mortars los ntxiv dag zog thiab tsim lub tsev, weave yarn los ntawm wool, thiab siv paj rwb, txhob lo lo ntxhuav, ntaub plaub thiab tsiaj tawv nqaij los tsim khaub ncaws. Ntuj organic polymers nrog txiv neej nyob rau hauv tag nrho cov theem ntawm nws tsim thiab kev loj hlob thiab nyob rau hauv ntau txoj kev pab nws ua tiav cov txiaj ntsig uas peb muaj hnub no.

Xwm nws tus kheej tau muab txhua yam los ua kom tib neeg lub neej xis nyob li sai tau. Thaum lub sij hawm, roj hmab tau pom, nws cov khoom zoo kawg nkaus tau qhia meej. Txiv neej tau kawm siv cov hmoov txhuv nplej siab rau zaub mov, thiab cellulose rau kev siv tshuab. Camphor kuj yog ib tug natural polymer, uas kuj tau paub txij thaum ancient sij hawm. Resins, proteins, nucleic acids yog tag nrho cov piv txwv ntawm cov tebchaw nyob rau hauv kev xav.

qauv ntawm natural polymers

Tsis yog txhua tus neeg sawv cev ntawm chav kawm ntawm cov tshuaj no muaj cov qauv zoo ib yam. Yog li, ntuj thiab hluavtaws polymers tuaj yeem sib txawv heev. Lawv cov molecules yog taw qhia nyob rau hauv xws li ib txoj kev uas nws yog qhov zoo tshaj plaws thiab yooj yim kom muaj nyob los ntawm lub zog ntawm qhov pom. Nyob rau tib lub sijhawm, ntau hom tsiaj muaj peev xwm o thiab lawv cov qauv hloov hauv cov txheej txheem. Muaj ntau ntau qhov sib txawv ntawm cov qauv saw:

• linear;
• nplooj;
• star-shaped;
• flat;
• mesh;
• tape;

Nyob zoo ib tsoom phooj ywg.

Cov neeg sawv cev ntawm cov khoom siv dag zog thiab hluavtaws ntawm macromolecules muaj qhov loj heev, muaj pes tsawg tus atoms. Lawv raug tsim nrog tshwj xeeb cov khoom tshwj xeeb. Yog li ntawd, lawv cov qauv yog Ameslikas npaj los ntawm tus txiv neej. Natural polymers feem ntau yog linear lossis reticulated hauv cov qauv.

Piv txwv ntawm ntuj macromolecules

Natural thiab artificial polymers yog ze rau ib leeg. Tom qab tag nrho, thawj zaug ua lub hauv paus rau kev tsim ntawm qhov thib ob. Muaj ntau yam piv txwv ntawm kev hloov pauv zoo li no. Ntawm no yog ib co ntawm lawv.

1. Ordinary milky-dawb yas yog cov khoom tau los ntawm kev kho cellulose nrog nitric acid nrog ntxiv ntawm natural camphor. Cov tshuaj tiv thaiv polymerization ua rau cov txiaj ntsig polymer kom khov thiab dhau los ua cov khoom xav tau. Thiab cov plasticizer - camphor, ua rau nws muaj peev xwm muag thaum cua sov thiab hloov nws cov duab.
2. Acetate txhob lo lo ntxhuav, tooj liab-ammonia fiber, viscose yog tag nrho cov piv txwv ntawm cov xov, fibers uas tau los ntawm cellulose. Npuag ua los ntawm ntuj paj rwb thiab linen tsis yog li ruaj, tsis ci, yooj yim wrinkled. Tab sis cov analogues dag ntawm lawv tsis muaj qhov tsis txaus, uas ua rau lawv siv tau zoo heev.
3. Pob zeb cuav, cov khoom siv hauv tsev, cov khoom sib xyaw, cov tawv hloov pauv yogSaib cov piv txwv ntawm cov polymers muab tau los ntawm cov khoom siv raw.

Cov tshuaj, uas yog ib yam khoom ntuj tsim, kuj tuaj yeem siv rau hauv nws daim ntawv tseeb. Kuj tseem muaj ntau yam piv txwv:

• rosin;
• amber;
• starch;
• amylopectin;
• cellulose;
• fur;
• wool;
• paj;
• silk;
• cement;
• clay;
• lime;
• proteins;
• nucleic acids thiab lwm yam.

Pom tseeb, chav kawm ntawm cov khoom sib txuas peb tab tom txiav txim siab yog ntau heev, xyaum ua thiab tseem ceeb rau tib neeg. Tam sim no cia peb saib ntau dua cov neeg sawv cev ntawm ntuj polymers, uas yog qhov xav tau zoo nyob rau lub sijhawm tam sim no.

Cov mis ntawm ntuj txhob lo lo ntxhuav polymer yog complex, vim nws cov tshuaj muaj pes tsawg leeg yog qhia los ntawm cov nram qab no Cheebtsam:

• fibroin;
• sericin;
• waxes;
• fats.

Lub ntsiab protein nws tus kheej, fibroin, muaj ntau hom amino acids. Yog tias koj xav txog nws cov saw hlau polypeptide, ces nws yuav zoo li no: (-NH-CH₂-CO-NH-CH(CH₃)- CO-NH-CH₂-CO-)_n. Thiab qhov no tsuas yog ib feem ntawm nws. Yog tias peb xav txog tias qhov sib npaug ntawm sericin protein molecule txuas nrog cov qauv no nrog kev pab los ntawm van der Waals rog, thiab ua ke lawv sib xyaw ua ke rau hauv ib qho kev sib haum xeeb nrog cov quav thiab cov rog, ces nws yog qhov tseeb tias vim li cas nws nyuaj rau piav qhia txog cov mis. ntawm natural silk.

Rau hnub noNiaj hnub no, feem ntau ntawm cov khoom no yog muab los ntawm Tuam Tshoj, vim hais tias nyob rau hauv nws qhib qhov chaw muaj ib tug natural chaw nyob rau lub ntsiab tsim khoom - lub silkworm. Yav dhau los, pib los ntawm feem ntau ancient sij hawm, ntuj txhob lo lo ntxhuav muaj nuj nqis heev. Tsuas yog cov neeg nplua nuj, cov neeg nplua nuj tuaj yeem them tau khaub ncaws los ntawm nws. Niaj hnub no, ntau yam ntawm cov ntaub no tawm ntau yam xav tau. Piv txwv li, nws yog magnetized heev thiab wrinkled, nyob rau hauv tas li ntawd, nws poob nws luster thiab ploj los ntawm raug rau lub hnub. Yog li ntawd, cov khoom siv dag zog raws li nws siv ntau dua.

Wool kuj yog ib yam khoom ntuj tsim, vim nws yog cov khoom pov tseg ntawm daim tawv nqaij thiab qog sebaceous ntawm cov tsiaj. Raws li cov khoom lag luam protein no, knitwear yog tsim, uas, zoo li cov ntaub lo lo ntxhuav, yog cov khoom muaj txiaj ntsig.

Starch

Natural polymer starch yog cov khoom pov tseg ntawm cov nroj tsuag. Lawv tsim nws los ntawm cov txheej txheem ntawm photosynthesis thiab sau nyob rau hauv ntau qhov chaw ntawm lub cev. Nws cov tshuaj muaj pes tsawg leeg:

• amylopectin;
• amylose;
• alpha-glucose.

Cov qauv ntawm cov hmoov txhuv nplej siab yog cov ceg tawv heev, tsis zoo. Ua tsaug rau amylopectin muaj nyob rau hauv cov muaj pes tsawg leeg, nws muaj peev xwm swell nyob rau hauv dej, tig mus rau hauv lub thiaj li hu ua muab tshuaj txhuam. Cov tshuaj colloidal no yog siv hauv engineering thiab kev lag luam. Tshuaj, kev lag luam khoom noj khoom haus, kev tsim cov ntawv nplaum nplaum kuj yog qhov chaw siv rau cov khoom no.

Ntawm cov nroj tsuag uas muaj cov hmoov txhuv nplej siab tshaj plaws, peb tuaj yeem paub qhov txawv:

• pob kws;
• qos;
• rice;
• nqaij;
• cassava;
• oats;
• buckwheat;
• bananas;

Raws li biopolymer no, cij ci, pasta yog tsim, kissels, cereals thiab lwm yam khoom noj khoom haus yog siav.

Pulp

Los ntawm qhov kev xav ntawm chemistry, cov tshuaj no yog ib qho polymer, muaj pes tsawg leeg ntawm cov qauv qhia (C₆H _{5 O} 5_{) . Qhov sib txuas monomeric hauv cov saw hlau yog beta-glucose. Cov chaw tseem ceeb ntawm cov ntsiab lus cellulose yog cov phab ntsa ntawm tes ntawm cov nroj tsuag. Vim li ntawd, ntoo yog qhov muaj txiaj ntsig ntawm qhov sib xyaw no.}

Cellulose yog lub ntuj tsim polymer uas muaj cov qauv tsim tawm. Nws yog siv los tsim cov khoom hauv qab no:

• khoom siv pulp thiab ntawv;
• faux fur;
• sib txawv ntawm cov khoom siv dag zog;
• paj;
• plastics;
• hmoov tsis tswm;
• daim tawv nqaij thiab lwm yam.

Pom tseeb, nws qhov tseem ceeb ntawm kev lag luam yog qhov zoo. Nyob rau hauv thiaj li yuav muab ib tug compound siv nyob rau hauv ntau lawm, nws yuav tsum xub muab rho tawm los ntawm cov nroj tsuag. Qhov no yog ua los ntawm kev ua noj ntev ntev ntawm cov ntoo hauv cov khoom siv tshwj xeeb. Kev ua haujlwm ntxiv, nrog rau cov reagents siv rau kev zom zaub mov, sib txawv. Muaj ntau txoj hauv kev:

• sulfite;
• nitrate;
• sodium;
• sulfate.

Tom qab kev kho mob no, cov khoom tseem muajimpurities. Nws yog nyob ntawm lignin thiab hemicellulose. Yuav kom tshem tau ntawm lawv, qhov loj yog kho nrog chlorine lossis alkali.

Nyob hauv tib neeg lub cev tsis muaj cov khoom siv roj ntsha uas yuav ua kom tawg tau qhov nyuaj biopolymer. Txawm li cas los xij, qee cov tsiaj txhu (herbivores) tau yoog rau qhov no. Lawv muaj qee yam kab mob hauv lawv lub plab uas ua rau lawv. Nyob rau hauv rov qab, microorganisms tau txais lub zog rau lub neej thiab chaw nyob. Daim ntawv symbiosis no muaj txiaj ntsig zoo rau ob tog.

Rubber

Nov yog lub ntuj polymer ntawm kev lag luam tseem ceeb. Nws tau piav qhia thawj zaug los ntawm Robert Cook, uas pom nws hauv ib qho ntawm nws txoj kev mus ncig. Nws tshwm sim li no. Tau tsaws rau ntawm ib lub koog pov txwv uas cov neeg tsis paub txog nws, nws tau txais tos txais los ntawm lawv. Nws qhov kev xav tau nyiam los ntawm cov menyuam yaus hauv zos uas tau ua si nrog ib qho khoom txawv txawv. Lub cev kheej kheej no ncaws tawm hauv pem teb thiab thaws siab, ces rov qab.

Thaum nug cov pej xeem hauv zos tias cov khoom ua si no yog dab tsi, Cook kawm tau tias cov kua txiv hmab txiv ntoo ntawm ib tsob ntoo, hevea, hardens li no. Ntau tom qab nws tau pom tias qhov no yog roj hmab biopolymer.

Cov tshuaj lom neeg ntawm cov khoom sib xyaw no paub - nws yog isoprene uas tau dhau los ua ntuj tsim polymerization. Cov qauv roj hmab yog (С₅Н₈) _{. Nws cov khoom uas ua rau nws zoo siab heev yog raws li hauv qab no:}

• elasticity;
• hnav resistant;
• hluav taws xob rwb thaiv tsev;

dej resistant.

Txawm li cas los xij, kuj muaj qhov tsis zoo. Nyob rau hauv lub txias, nws yuav nkig thiab nkig, thiab nyob rau hauv lub tshav kub, nws yuav nplaum thiab viscous. Tias yog vim li cas nws thiaj li tsim nyog los tsim cov analogues ntawm cov khoom siv dag zog lossis hluavtaws. Niaj hnub no, rubbers tau dav siv rau kev siv tshuab thiab kev lag luam. Cov khoom tseem ceeb tshaj plaws raws li lawv:

• rubbers;
• ebonites.

Amber

Nws yog ib yam khoom ntuj polymer, vim hais tias nyob rau hauv nws cov qauv nws yog ib tug resin, nws fossil daim ntawv. Lub spatial qauv yog ib tug ncej amorphous polymer. Nws yog heev flammable thiab yuav ignited nrog ib tug match nplaim. Nws muaj luminescence zog. Qhov no yog ib qho tseem ceeb heev thiab muaj txiaj ntsig zoo uas yog siv rau hauv cov hniav nyiaj hniav kub. Cov hniav nyiaj hniav kub raws li amber yog qhov zoo nkauj heev thiab xav tau.

Ntxiv rau, qhov biopolymer no kuj siv rau kev kho mob. Nws kuj yog siv los ua cov ntawv xuab zeb, cov kua roj vanish rau ntau qhov chaw.