Oligomer molecules

The presence of one carbonyl group per oligomer molecule was also ascertained. The orange colour of the resin suggested that some minor event during the photopolymerization produced chromophores in small concentrations. The presence of furoin among the products corroborated the proposed mechanism, which was shown not to involve free radical chain reactions. 

Hydroxy-terminated PDMS, however, has disadvantages. The monofunctional ends limit the number of connections between the polymer (or oligomer) molecule and the glass network to two. This limitation raises the possibility that some PDMS molecules are not tied at both ends to the glass network if the polycondensation does not go to completion i.e. there may be "dangling" or loose PDMS chains in the final sol-gel material. This occurance of free ends would indeed be anticipated since the extent of reaction most likely is not 100%. Hence, the physical properties, specifically the mechanical behavior of the overall material, would be expected to suffer as a result of loose PDMS chains in the system. Disregarding this potential problem, the mechanical behavior of the sol-gel hybrids are, ultimately, influenced by the mechanical behavior of the modifying elastomer ... 

Oligomer molecule, the structure of which essentially comprises the repetition of a single constitutional unit with all units connected identically with respect to directional sense. 

Largest constitutional unit contributed by a single monomer molecule to the structure of a macromolecule or oligomer molecule. 

Macromolecule or oligomer molecule that has one end-group which enables it to act as a monomer molecule, contributing only a single monomeric unit to a chain of the final macromolecule. 

Macromolecule or oligomer molecule capable of entering, through reactive groups, into further polymerization, thereby contributing more than one constitutional unit to at least one type of chain of the final macromolecules. 

Number of monomeric units in a macromolecule an oligomer molecule, a block, or a chain. 

Atom or group of atoms (with pendant atoms or groups, if any) comprising a part of the essential structure of a macromolecule, an oligomer molecule, a block, or a chain. 

Smallest constitutional unit, the repetition of which constitutes a regular macromolecule, a regular oligomer molecule, a regular block, or a regular chain. 

Whole or part of a macromolecule, an oligomer molecule, or a block, comprising a linear or branched sequence of constitutional units between two boundary constitutional units, each of which may be either an end-group, a branch point, or an otherwise-designated characteristic feature of the macromolecule. 

Numher of covalent bonds emanating from a constitutional unit of an oligomer molecule or a macromolecule. 

Number of covalent bonds that a monomer molecule or monomeric unit (see Definition 1.8 in [1]) in a macromolecule or oligomer molecule can form with other reactants. 

Polymer or oligomer whose molecules each have one end-group that acts as a monomer molecule, so that each polymer or oligomer molecule contributes only a single monomer unit to a chain of the product polymer. 

The trimer showed the peaks of 127, 158 and 258, while the dimer showed the peaks of 127 and 158. The results strongly indicate that the ketone unit locates at the chain end of the oligomer, which could not be determined by NMR spectroscopy. Then, it is reasonable to assume that the oligomer molecule containing a terminal methine proton has one butyl isopropenyl ketone unit at the chain end. 

In the case of oligomers, the concept of number-average functionality, fn, is usually applied, which is the ratio between the total number of functional groups and the total number of molecules in the system, or, in other words, the average number of RFG per initial oligomer molecule. 

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