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- Practical Guide -
Page 43 of 153
3.3.1.9 "Blend" means any mixture of polymers and/or plastics in the same physical state, each of which can be used as
such for the manufacture of finished materials and articles.
3.3.1.10 "Basic polymer" means any polymeric substance, such as plastic or polymer, which is capable of functioning
as the main structural component of finished materials and articles."
Note
The definition of "basic polymer" includes both definitions of "plastic" (...which may contain additives) and
"polymer"(...which does not contain additives).
It should be remembered that basic polymers should comply
with the requirements specified in sub-paragraph 4.2 i.e. - in practice - they should follow the rules of Directive
2002/72/EC.
3.3.1.11
"
Additive" means a substance, which is incorporated into plastics to achieve a technical effect in the finished
product; they are intended to be present in the finished articles.
Note
Sometimes in the text is used the expression "conventional additive" to indicate the additives which have no a
polymeric structure.
3.3.1.12 "Polymer production aids" means any substance used to provide a suitable medium in which polymerisation
occurs (e.g. emulsifiers, surfactants, buffering agents, etc.)
3.3.2. Status of oligomers and pre-polymers used as "monomers or starting substances"
Annex 2 of Directive 2002/72/EC establishes that the list of monomers and other starting
substances includes natural or synthetic macromolecular substances used for the manufacture
of modified macromolecules, if the monomers or the other starting substances required for
their synthesis are not listed (e.g. polyvinylalcohol, as vinylalcohol is non existent)
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.
It has been stated in 2.1.2 and 2.1.3 of Annex 2 of Directive 2002/72/EC that oligomers and
natural or synthetic macromolecular substances (e.g. pre-polymers), as well as their mixtures,
are not listed if the monomers or starting substances required for their synthesis are included
in the list.
It must be stressed that "blends of the approved polymers used as starting substances" are
automatically authorised and, therefore, are not listed.
3.3.3 Status of polymeric additives as defined under 4.1
When used as additives, oligomers and natural or synthetic macromolecular substances as
well as their mixtures are all included in the list, even if the monomers or starting substances
required for their synthesis are included in the list.
Nota bene
It must be stressed that any polymer which can be used as such for the manufacture of finished materials and
articles is excluded by the definition of polymeric additive.
3.3.4 Why the difference in treating oligomers and (pre-)polymers?
Why are oligomers and polymers treated differently when their monomers are listed
compounds? When oligomers and pre-polymers are used as "monomer or starting
substances", they are largely converted to high molecular weight polymers, which are no risk
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See Annex 2 of the Directive.