Mienzaniso yeMibvunzo Inokurukura nezveKuwedzera Polymerization
Polymerization inzira iyo mamonomers—mamorekuru madiki ane maumbirwo akafanana—anobatana kuti aumbe mamorekuru makuru anonzi mapolymer. Kune mhando mbiri huru dzepolymerization: addition polymerization uye condensation polymerization. Chinyorwa chino chichakurukura rumwe rwemhando idzi, addition polymerization, nekusimbisa mienzaniso nekukurukurirana kuti tipe kunzwisisa kwakadzama kwepfungwa iyi.
Kunzwisisa Kuwedzera Polymerization
Kuwedzera polymerization inzira iyo mamonomer anobatana pasina kurasikirwa nemamorekuru madiki akadai semvura kana HCl. Mamonomer anowanzobatanidzwa mukuwedzera polymerization ialkenes uye polarized alkenes, ane carbon-carbon (C=C) double bonds. Kana mamonomer aya achipindura, double bonds dzinotyoka, zvichiita kuti mamonomer abatane kuita cheni refu.
Mienzaniso yemapolymer akagadzirwa nekuwedzera polymerization inosanganisira polyethylene (PE), polypropylene (PP), polystyrene (PS), uye polyvinyl chloride (PVC). Mapolymer ese aya akakosha muindasitiri uye muhupenyu hwezuva nezuva nekuda kwesimba rawo, kugadzikana, uye kushandiswa kwakasiyana-siyana.
Maitiro ekuwedzera ePolymerization
Maitiro ekuwedzera polymerization anogona kukamurwa kuita matanho makuru matatu:
1. Kutanga: Danho apo ma free radicals kana ma ions anoumbwa kuti atange reaction.
2. Kupararira: Danho apo monomers dzinoramba dzichibatana kuti dzigadzire cheni refu.
3. Kuguma: Danho apo reaction inomira nekuti cheni mbiri dzefree radical dzinobatana kana kuti free radicals dzinosangana nechinhu chinodzivisa.
Kuti zvijekeswe, heino hurukuro yemienzaniso yakati wandei yemibvunzo yekuwedzera polymerization.
Mibvunzo yemuenzaniso nekukurukurirana
Mubvunzo 1: Kugadziriswa kwePolyethylene
Mubvunzo: Tsanangura maitiro ekuwedzera polymerization ye ethylene (C2H4) kuti igadzire polyethylene (PE), sanganisira reaction equation inoitika.
Kukurukurirana:
- Kutanga:
Kutanga kunogona kuitwa uchishandisa ma catalysts kana ma free radicals. Ngatitii tiri kushandisa ma free radicals. Ma radical initiators akaita se benzoyl peroxide (C14H10O4) anogona kuburitsa ma free radicals kana apiswa.
\[
C14H10O4 \rightarrow 2C6H5COO^{\cdot}
\]
- Kupararira:
Ma radical aya acharwisa ma bond maviri ari mu ethylene monomer, zvichigadzira ma radical matsva anogona kuramba achirwisa monomer inotevera.
\[
R^{\cdot} + CH2=CH2 \museve wekurudyi R-CH2-CH2^{\cdot}
\]
Tevere, ma radical ari pamagumo echeni acharamba achiwedzera ethylene monomers kuitira kuti cheni yacho irebe.
\[
R-CH2-CH2^{\cdot} + nCH2=CH2 \rightarrow R-(CH2-CH2)_n^{\cdot}
\]
- Kugumiswa:
Kuguma kunogona kuitika kuburikidza nekusanganiswa kwecheni mbiri dzema radical kana nekuita pakati pe radical ne inhibitor.
\[
R-(CH2-CH2)_n^{\cdot} + R-(CH2-CH2)_m^{\cdot} \rightarrow R-(CH2-CH2)_{n+m}-R
\]
Mugumisiro wacho ipolyethylene (PE), polymer inogadzirwa nekubatanidza akawanda ethylene monomers (\(n\) ethylene).
Mubvunzo 2: Kugadziriswa kwePolystyrene
Mubvunzo: Indasitiri yemakemikari inoda kugadzira polymer kubva ku monomer styrene (C8H8). Tsanangura maitiro e polymerization anoitika uye nyora chimiro che polystyrene.
Kukurukurirana:
- Kutanga:
Sezvinoita polyethylene, ma free radicals anodiwa kuti atange reaction. Ngatitii tinoshandisa peroxide radicals.
\[
ROOR \museve wekurudyi 2RO^{\cdot}
\]
- Kupararira:
Mafree radicals anorwisa ma styrene monomers ane carbon-carbon double bonds.
\[
RO^{\cdot} + C6H5-CH=CH2 \rightarrow RO-C6H5-CH^{\cdot}-CH3
\]
Danho rekupararira richaunza ma radical aya kuti arambe achirwisa mamwe ma monomers e styrene.
\[
RO-C6H5-CH^{\cdot}-CH3 + n(C6H5-CH=CH2) \rightarrow RO-(C6H5-CH-CH2)_n-C6H5-CH^{\cdot}-CH3
\]
- Kugumiswa:
Kuguma kunoitika kana cheni mbiri dze polymer dzakasimba dzasangana.
\[
RO-(C6H5-CH-CH2)_n^{\cdot} + RO-(C6H5-CH-CH2)_m^{\cdot} \rightarrow RO-(C6H5-CH-CH2)_{n+m}-RO
\]
Chimiro chepolystyrene (PS) chinobuda icheni refu ine mayuniti emonomer anodzokororwa.
Mubvunzo 3: Kugadziriswa kwePolyvinyl Chloride (PVC)
Mubvunzo: Tsanangura kuwedzera kwe vinyl chloride monomer (C2H3Cl), uye ipa mienzaniso yekushandiswa kwe polyvinyl chloride (PVC).
Kukurukurirana:
- Kutanga:
Kufanana nemuenzaniso wapfuura, ma free radicals anogadzirwa kubva ku peroxides.
\[
ROOR \rightarrow 2R-O^{\cdot}
\]
- Kupararira:
Mafree radicals anorwisa ma "double bonds" ari muma "vinyl chloride monomers".
\[
RO^{\cdot} + CH2=CHCl \museve wekurudyi RO-CH2-CHCl^{\cdot}
\]
Kupararira kunoenderera mberi nekubatana kwemayuniti emonomer kuti awedzere cheni yacho.
\[
RO-CH2-CHCl^{\cdot} + nCH2=CHCl \rightarrow RO-(CH2-CHCl)_n^{\cdot}
\]
- Kugumiswa:
Kuguma kunoitika kana ma "radical chains" maviri abatana.
\[
RO-(CH2-CHCl)_n^{\cdot} + RO-(CH2-CHCl)_m^{\cdot} \rightarrow RO-(CH2-CHCl)_{n+m}-RO
\]
Polyvinyl chloride (PVC) ipolymer inogadzirwa uye inoshandiswa muzvinhu zvakasiyana-siyana zvakaita semapaipi emvura, tambo dzemagetsi, nezvimwe zvigadzirwa zvepurasitiki zvakasiyana-siyana.
Mhedziso
Kuwedzera polymerization inzira yakakosha yemakemikari inosanganisira kusanganiswa kwemamonomers pasina kuburitswa kwemamorekuru madiki. Kunzwisisa mashandiro uye maitiro ekuwedzera polymerization, senge ayo anoonekwa mu polyethylene, polystyrene, uye PVC, kunotibatsira kudzidza nekushandisa ruzivo urwu mumaindasitiri uye muhupenyu hwezuva nezuva. Kuburikidza nemienzaniso iyi nehurukuro, tinogona kuwana kunzwisisa kwakadzama kwemaitiro nezvigadzirwa zvinobva mukuwedzera polymerization, pamwe nemashandisirwo ayo anoshanda anokanganisa tekinoroji nehupenyu hwemazuva ano.
