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Hyperbranched bis-MPA polyester-64-hydroxyl Preparation Procedure

Product Description


Theoretical MW : 7323 g/mol
Average Molecular Formula : C315H512O189
Number of hydroxyl groups : 64 (average)


This polydisperse compound has multiple surface hydroxyl groups. The hydroxyl groups are selectively reactive with anhydrides or acyl halides. This material can be used as:

  • precursor for synthesis of dendritic-linear materials
  • polyfunctional initiator for ring-opening polymerizations
  • polyfunctional cross-linker for thermosets


High degree of branching results in high solubility and low viscosity (solution and melt). The compound is transparent to light in the UV/Vis wavelength region.

The product is highly purified by multiple precipitations and is supplied as a freeze-dried, white powder. It may contain traces of methanol or ether.

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Precautions and Disclaimer

This product is for R&D use only, not for drug, household, or other uses. Please consult the Safety Data Sheet for information regarding hazards and safe handling practices.

Preparation Instructions

The product is soluble in polar organic solvents (warm THF, DMSO, DMF, and methanol) and water.

Storage/Stability

Store the product at room temperature.

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Procedure

Acylation of the hydroxyl end groups:

  1. Dissolve the hyperbranched polyester in THF (calculate nOH using the theoretical MW), and add triethylamine (1.2 ´ nOH) and a catalytic amount of 4-(dimethylamino) pyridine (Catalog Number 522805).
  2. Put the flask on an ice/water bath and add the acylation reagent while stirring. Let the reaction reach completion and perform work -up as required (typically through extraction, requires change of solvent).
  3. Evaporate to dryness using a rotary evaporator.

Hydroxyl groups as initiators for ring-opening polymerization of lactones:

  1. Dissolve the dried hyperbranched polyester in toluene and add the required amount of tin(II) 2-ethylhexanoate [Sn(Oct)2] (Catalog Number S3252) and distilled e-caprolactone (Catalog Number 241296) in the required amount. Exclude moisture by three repetitive vacuum cycles.
  2. Put the flask in a preheated oil bath and let the polymerization reach the desired conversion.
  3. Dissolve the product in THF and precipitate into cold methanol. Isolate the product by filtration.

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Related Products

Hyperbranched bis-MPA polyester-16-hydroxyl, generation 2 (Catalog Number 686603)
Hyperbranched bis-MPA polyester-32-hydroxyl, generation 3 (Catalog Number 686581)

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Materials

     

References

  1. Claesson, H. et al., Synthesis and Characterization of Star Branched Polyesters with Dendritic Cores and the Effect of Structural Variations on Zero Shear Viscosity. Polymer, 43, 3511-3518 (2002).
  2. Arce, E. et al., Glycodendritic Structures Based on Boltorn Hyperbranched Polymers and Their Interactions with Lens culinaris Lectin. Bioconjugate Chem., 14, 817-823 (2003).

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