SELECTION OF DENDRIMERS AND HYPERBRANCED POLYMERS
By definition (see Abbasi et al.), “dendrimers are nano-sized, radially symmetric molecules with well-defined, homogeneous, and monodisperse structure that has a typically symmetric core, an inner shell, and an outer shell.” Hyperbranched polymers differ from dendrimers by their lack of the perfect branching pattern found in dendrimers. Dendrons, which are monodisperse molecules that branch out from a single focal point, are used in preparing dendrimers. See also Gupta and Nayak and Agrawal and Kulkarni for additional open access review articles.
The continued development of dendrimers, hyperbranched polymers, and their applications, remains at the frontiers of materials research and development (R&D). This post provides a perspective on the great diversity of commercially available dendrimers and hyperbranched polymers. Helping our clients select the best choices for their applications from among the vast number of such products falls under the scope of our material selection services.
Many companies supply dendrimers and/or hyperbranched polymers. The products offered by several of these suppliers will be discussed below. If a supplier is only a distributor of a product, the manufacturer of the product will also be identified.
Unless indicated otherwise, each image in this post is reproduced from the website of the supplier, or from the website of the manufacturer whose product the supplier is distributing, discussed in the paragraph immediately above the image.
Sigma-Aldrich sells a vast range of dendrimers and three hyperbranched polymers, mainly at relatively high prices and in small quantities, for use in R&D projects. It is often the best source for acquiring small samples of many different materials for use in the preliminary stages of the screening of candidates to identify promising options.
Dendritech was established in 1992 to commercialize the PAMAM (polyamidoamine) dendrimers developed at Dow Chemical by Dr. Donald A. Tomalia. Dendritech focuses on the development and the commercial-scale production of tailor-made dendrimers and hyperbranched polymers. It remains the global leader in the commercial supply of PAMAM dendrimers. Its products have exceptional molecular uniformity, compact nanoscale size, globular shape, and high surface group functionality. They function as designed linkers and delivery agents for a broad range of biological, organic, and inorganic materials. They enable commercial applications in both biomedical and industrial areas; including diagnostic, drug delivery, personal care, industrial coatings, and membrane separation markets.
NanoSynthons was founded by Dr. Tomalia in 2010 to explore new directions in dendrimer and hyperbranched polymer technology. It focuses on the development, production, and distribution of competitively priced high-purity dendrons and dendrimers. It uses greener, low-cost processes, and structural control over critical nanoscale design parameters including size, shape, surface chemistry, flexibility/rigidity, and molecular architecture, to accomplish these objectives. Its goal is to redefine the standards for dendrimer/dendron purity and to thus establish “gold standards” for the industry with competitive prices. It is dedicated to providing customers with the highest-purity materials available for their R&D needs. Its current commercial products are all PAMAM dendrimers. It also appears to be willing to develop customized new products to meet specific customer needs.
Polymer Factory claims to be currently the provider of the world’s largest library of advanced dendritic materials. Its strategy is to build values and revenues through the development, manufacturing, and sale of unique patented dendritic macromolecules. Its product portfolio includes monodisperse dendritic polymers built from 2,2-bis(methylol)propionic acid, such as the biocompatible bis-MPA dendrimers and dendrons. It is a global provider of both polyester (Boltorn™, developed by and sold in larger volumes by Perstorp) dendritic polymers and poly(ester amide) [members of Hybrane® family, see Froehling (2004), developed by and sold in larger volumes by DSM] hyperbranched polymers for research purposes. It also conducts contract research with focus on materials science and biomedical applications.
Starpharma is a leader in the development of dendrimer products for pharmaceutical, life science, and other applications. It offers the VivaGel® women’s health product portfolio, the DEP® Dendrimer Enhanced Product drug delivery portfolio and the VIRALEZE™ antiviral nasal spray. It is developing several products internally and others via sales and commercial partnerships. VivaGel® is based on SPL7013, astodrimer sodium, a proprietary dendrimer. DEP® has demonstrated reproducible preclinical benefits across multiple internal and partnered DEP® programs; including improved efficacy, safety, and survival.
The Rudolf Group has developed novel non-fluorocarbon polymer and hence more environmentally friendly hydrophobic textile finishes for imparting water repellency based on hyperbranched polymer technology. Hyperbranched, hydrophobic polymers with ramified structures (like in tree tops) orientate in an orderly manner on a textile surface and crystallize on specifically adjusted comb polymers. The optimum arrangement of many of these functional elements is highly effective. Additional boosters (crosslinking agents) ensure the optimum attachment and durability on many fibre substrates. Hyperbranched polymers are produced step by step by combining multifunctional components. With each synthetic step of these hyperbranched polymers, the number of reactive end groups grows exponentially. The specific control of reactions enables the functionalization of end groups with hydrophobic residues at the end of a series of synthetic steps, resulting in an extreme density of water-repellent groups. These hyperbranched, hydrophobic polymers are highly effective and, due to their network structure, they tend to self-organize and crystallize. For optimum orientation and attaching to the fiber surface, RUCO-DRY ECO® and RUCO-DRY ECO PLUS®, the finishing products of BIONIC-FINISH® ECO, not only use hyperbranched polymers but also specifically adjusted “comb“ polymers. The water-repellent effect level obtained by initial textile finishing has so far only been possible with fluorocarbon polymers.
DIC is a fine chemicals company. It was established in 1908 as a manufacturer of printing inks. Its products include Hybranch® hyperbranched polystyrene, a revolutionary thin polystyrene that resists tears and breaks. Hybranch® initially earned praise for its outstanding film-forming capability. Applications were later expanded to include foamed polystyrene and refrigerator trays. Customers who used the product in the production of molded items gave Hybranch® top marks for improving productivity, as well as for facilitating the production of lighter products, thereby providing cost benefits when recycled.