Maleamide

Other polymers like polypropylene or polystyrene modified by maleic anhydride or maleamide, with the add groups converted to amide, ester or ester chloride and then reacted on Nylon fibers, have been claimed in a Japanese patent (101). Two patents report grafting of olefinic polymers on polycaprolactam (102,103). Grafting of polysiloxanes on polyamides can be induced by X-rays (104). 

FIGURE 11. Hydrogen bonding (---) in (Ph4P)[Ni(mant)2] (madt = maleamide dithiolate). Reprinted with permission from Reference 67. Copyright 2005 American Chemical Society... 

Bis(julolidinyl)-ethylene-l, 2-dithiolate Laser Disc Read Only Memory Ligand to Ligand Charge Transfer Ligand to Metal Charge Transfer Lowest Unoccupied Molecular Orbital Maleamide-1,2-dithiolate... 

Maleamide Maleic acid diamide, malein-amide)... 

A molecular shuttle based on a bistable peptide [2]rotax-ane (Figure 64) with remarkable positional discrimination was also reported by the same gronp. The position of the tetraamide macrocycle can be altered by irradiation of light and recovered by heat due to the light-induced conformation change between fumaramide (trans) and maleamide (cis) isomers. 

Other types of rotary motors can be constructed using catenanes, that is, species minimally composed of two mechanically interlocked macrocycles. In appropriately designed systems, the rotation of one ring around the other can be achieved by external stimulation. If suitable control elements are introduced in the structure, such a rotation can be performed unidirectionally. This concept was cleverly realized with benzylic amide catenanes by exploiting the isomerization of fumaramide to maleamide caused by UV light. Chiral C=N compounds such as imines also fulfill the criteria of two-step light-driven unidirectional molecular... 

PROTEIN IMMOBILIZATION ONTO NEWLY DEVELOPED POLYURETHANE-MALEAMIDES FOR ENDOTHELIAL CELL GROWTH... 

For these reasons, among the family of segmented polyurethanes currently used in cardiovascular applications for their desirable properties, poly-urethane-maleamides (PUMAs) appear to be of particular interest. PUMAs are obtained with dicarbojQ lic acids as chain extenders, instead of traditional diols and diamines. The use of maleic acid as chain extender allows the insertion in the polymer chain of activated double bonds, which can perform as grafting sites for further derivatisation in aqueous solutions and mild conditions. ... 

Figure I. Schematic structure of poly-urethane-maleamides (PUMAs)...

PUMAs were extracted in ethanol, in order to remove lower molecular weight substances. After this treatment, PUMAs appear to promote cell adhesion and proliferation, in particular PCU D2HM (Table 2). The only exception is represented by PCU 02HM which inhibit cell proliferation. This result may be explained with a possible slow release of low molecular weigh substances, not extracted by ethanol, from the bulk of the material according to the high polidispersity value (d = 4.5) shown by this polyurethane-maleamide. 

Fibronectin binding onto PUMAs appears to be time dependent. After 2 hours of incubation, PUMAs absorb amounts of HFn comparable with Bionate (Table 3), while a 16 hours incubation promoted higher HFn-adsorption for PUMAs. This suggests that the functional groups present in the polyurelhane-maleamide backbone efficiently act to promote HFn adsorption onto the materials, with a slow kinetic profile. 

On most PUMAs HFn adsorption is significantly higher than onto the biomedical grade polyurethane Bionate, indicating that functional groups present in the polyurethane maleamide backbone play a role in the protein binding. 

In particular the polyurethane maleamide named PCU D2HM showed interesting properties a high HFn binding associated to good cytocompatibility results. 

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