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Chain termination

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can occur where the radical at the end of the growing chain can be transferred from the chain to an individual monomer unit causing a new chain to start growing and the previous chain to stop growing. With
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Termination by recombination increases the chain length and therefore the molecular weight of the final polymer.
607:{\displaystyle \ {\Bigl }\quad +\quad {\Bigl }\quad \longrightarrow \quad {\Bigl }\quad +\quad {\Bigl }} 729: 641: 386: 103: 150: 636: 94: 90: 43: 618:
since it involves breaking of one bond, and therefore is more important at higher energy.
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step, one radical transfers a hydrogen atom to the other to form two stable molecules:
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The termination steps of free radical polymerization steps are of two types:
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Chemical reaction in which a chain carrier is converted irreversibly into
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a non-propagating species without the formation of a new chain carrier.
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Ability of some chain polymerization reactions to halt themselves
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Jenkins, Aubrey D.; Jones, Richard G.; Moad, Graeme (2010).
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Termination by disproportionation usually has a higher
397: 169: 606: 374: 133:which is then no longer reactive with the polyol. 599: 578: 577: 576: 575: 570: 558: 527: 526: 525: 524: 519: 507: 469: 468: 467: 466: 461: 449: 411: 410: 409: 408: 403: 367: 364: 363: 362: 361: 299: 298: 297: 296: 291: 279: 241: 240: 239: 238: 233: 221: 183: 182: 181: 180: 175: 721: 634: 72: 678: 676: 674: 654: 113:can be used to stop a reaction between a 689:(3rd ed., Prentice Hall 2003), p.70-72 722: 671: 137:Termination of radical polymerization 54:, effectively bringing it to a halt. 19:For the DNA sequencing method, see 13: 14: 741: 703: 567: 563: 516: 512: 458: 454: 288: 284: 230: 226: 121:because it will react with the 687:Contemporary Polymer Chemistry 628: 513: 285: 85:reactions is the depletion of 1: 621: 42:that ceases the formation of 7: 10: 746: 642:Pure and Applied Chemistry 104:step-growth polymerization 18: 73:Mechanisms of termination 656:10.1351/PAC-REP-08-04-03 153:step, two growing chain 50:step in the course of a 685:and Frederick W. Lampe 608: 376: 95:anionic polymerization 69: 44:reactive intermediates 609: 377: 63: 395: 167: 546: 488: 430: 352: 318: 261: 203: 25:nucleoside analogue 604: 534: 476: 418: 387:disproportionation 372: 340: 306: 249: 191: 147:disproportionation 131:R−(N−H)−(C=O)−O−R' 730:Polymer chemistry 616:activation energy 595: 587: 554: 537: 497: 479: 439: 421: 400: 343: 334: 326: 309: 269: 252: 211: 194: 172: 79:polymer chemistry 48:chain propagation 40:chemical reaction 36:chain termination 32:polymer chemistry 21:Sanger sequencing 737: 697: 683:Harry R. Allcock 680: 669: 668: 658: 632: 613: 611: 610: 605: 603: 602: 596: 593: 592: 585: 584: 574: 573: 562: 561: 555: 552: 551: 545: 542: 535: 533: 523: 522: 511: 510: 504: 503: 502: 495: 493: 487: 484: 477: 475: 465: 464: 453: 452: 446: 445: 444: 437: 435: 429: 426: 419: 417: 407: 406: 398: 381: 379: 378: 373: 371: 370: 360: 359: 354: 351: 348: 341: 339: 332: 331: 324: 323: 317: 314: 307: 305: 295: 294: 283: 282: 276: 275: 270: 267: 266: 260: 257: 250: 248: 237: 236: 225: 224: 218: 217: 212: 209: 208: 202: 199: 192: 190: 179: 178: 170: 132: 128: 112: 745: 744: 740: 739: 738: 736: 735: 734: 720: 719: 706: 701: 700: 681: 672: 633: 629: 624: 598: 597: 588: 580: 579: 569: 568: 557: 556: 547: 543: 538: 529: 528: 518: 517: 506: 505: 498: 494: 489: 485: 480: 471: 470: 460: 459: 448: 447: 440: 436: 431: 427: 422: 413: 412: 402: 401: 396: 393: 392: 366: 365: 355: 353: 349: 344: 335: 327: 319: 315: 310: 301: 300: 290: 289: 278: 277: 271: 262: 258: 253: 244: 243: 242: 232: 231: 220: 219: 213: 204: 200: 195: 186: 185: 184: 174: 173: 168: 165: 164: 139: 130: 126: 110: 75: 70: 66: 62: 28: 17: 12: 11: 5: 743: 733: 732: 718: 717: 705: 704:External links 702: 699: 698: 670: 649:(2): 483–491. 626: 625: 623: 620: 601: 591: 583: 572: 566: 560: 550: 541: 532: 521: 515: 509: 501: 492: 483: 474: 463: 457: 451: 443: 434: 425: 416: 405: 369: 358: 347: 338: 330: 322: 313: 304: 293: 287: 281: 274: 265: 256: 247: 235: 229: 223: 216: 207: 198: 189: 177: 138: 135: 125:functionality 115:polyisocyanate 99:chain transfer 74: 71: 57: 56: 52:polymerization 15: 9: 6: 4: 3: 2: 742: 731: 728: 727: 725: 716: 712: 708: 707: 696: 695:0-13-065056-0 692: 688: 684: 679: 677: 675: 666: 662: 657: 652: 648: 644: 643: 638: 631: 627: 619: 617: 589: 581: 564: 548: 539: 530: 499: 490: 481: 472: 455: 441: 432: 423: 414: 390: 388: 383: 356: 345: 336: 328: 320: 311: 302: 272: 263: 254: 245: 227: 214: 205: 196: 187: 162: 160: 159:vinyl polymer 156: 152: 151:recombination 148: 144: 143:recombination 134: 124: 120: 116: 109: 105: 100: 96: 92: 88: 84: 80: 68: 60: 55: 53: 49: 45: 41: 37: 33: 26: 22: 713:definition: 686: 646: 640: 630: 391: 384: 163: 146: 142: 140: 76: 64: 35: 29: 715:Termination 129:to produce 622:References 123:isocyanate 61:definition 711:Gold Book 582:− 549:− 531:− 514:⟶ 500:∙ 491:− 473:− 442:∙ 433:− 415:− 357:− 337:− 329:− 321:− 303:− 286:⟶ 273:∙ 264:− 246:− 215:∙ 206:− 188:− 724:Category 665:98243937 155:radicals 149:. In a 127:R−N=C=O 108:alcohol 91:radical 87:monomer 83:polymer 38:is any 709:IUPAC 693:  663:  399:  171:  119:polyol 117:and a 661:S2CID 385:In a 111:R'−OH 59:IUPAC 46:in a 691:ISBN 145:and 23:and 651:doi 594:CHX 553:CHX 496:CHX 438:CHX 333:CHX 325:CHX 268:CHX 210:CHX 161:, 93:or 77:In 30:In 726:: 673:^ 659:. 647:82 645:. 639:. 586:CH 536:CH 478:CH 420:CH 342:CH 308:CH 251:CH 193:CH 97:, 34:, 667:. 653:: 600:] 590:= 571:[ 565:+ 559:] 540:2 520:[ 508:] 482:2 462:[ 456:+ 450:] 424:2 404:[ 368:] 346:2 312:2 292:[ 280:] 255:2 234:[ 228:+ 222:] 197:2 176:[ 27:.

Index

Sanger sequencing
nucleoside analogue
polymer chemistry
chemical reaction
reactive intermediates
chain propagation
polymerization
IUPAC
polymer chemistry
polymer
monomer
radical
anionic polymerization
chain transfer
step-growth polymerization
alcohol
polyisocyanate
polyol
isocyanate
recombination
radicals
vinyl polymer
disproportionation
activation energy
"Terminology for reversible-deactivation radical polymerization previously called "controlled" radical or "living" radical polymerization (IUPAC Recommendations 2010)"
Pure and Applied Chemistry
doi
10.1351/PAC-REP-08-04-03
S2CID
98243937

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