Basic Considerations :
Polymer is a substance composed of macromolecules, built by covalently joining at least 50 molecular mers, or the Constitutional Repeating Units or CRU. The longest sequence of CRU defines the main chain of a macromolecule.
The main chain may be composed of a series of subchains, identified by some chemical of physical characteristic (e.g., tactic placement).
The main chain may also contain long or short side chains or branches, attached to it at the branch points.
A small region in a macromolecule from which at least four chains emanate constitutes a crosslinking point.
A macromolecule that has only one crosslink is the star macromolecule.
A macromolecule consisting of several crosslinked chains, but having a finite molecular weight is a micronetwork.
A highly ramified macromolecule in which each CRU is connected to every other CRU is a polymer network. When the main chain of a macromolecule has numerous branch points from which linear side chains emanate, it is comb macromolecule.
The CRU is not necessarily identical to the source from which the macromolecule was prepared — it is the largest identifiable group in the polymer.
To discuss the structure of polymer molecule
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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