Technical requirements exist for the desired properties of adhesives for use on human skin and/or mucosal tissues

Technical requirements exist for the desired properties of adhesives for use on human skin and/or mucosal tissues.

“Bioadhesiveness” is defined as a biological tissue that is highly hydrated. For example, the pressure-sensitive adhesion of mucosal tissue. In contrast, to conventional Psas (rubber, polysiloxane, and acrylates), which bond primarily to dry substrates, bioadhesives (BA) exhibit good viscosity when bonded to hydrated biological substrates.

As a bioadhesive, water should provide a plasticizing effect on the polymer, i.e. the polymer should be hydrophilic. For example, the general BA range includes partially crosslinked polyacrylates and polymethacrylate (EP0371421) and hydrophilic cellulose derivatives (40-95%) in blends with ethylene glycol (PEG). When the cross-linked polymer expands in sufficient amounts of water, the bioadhesive becomes sticky. the cohesive strength of highly cohesive hydrophilic compounds is usually very low, and BA differs from PSA in this respect.

For a variety of practical applications, it is very useful to have a batch of PSA and BA polymer materials with different hydrophilic properties, thus having different solubility in water or in the fluids excreted by the skin and mucous membranes (sweat, mucus, saliva, etc.). Biegajski et al described the performance of combining class PSA with Class BA in US Patent 5700478.

The combined attempt, in which a water-soluble pressure-sensitive mucosal adhesive was obtained by mixing 95-40% polyethylpyriloidone (PVP) with 0-50% hydroxypropyl cellulose (HPC) and 11-60% glycerin. Other examples of hydrophilic polymer mixtures with PSA and BA composition properties include polyacrylate-polyvinyl alcohol (PAA-PVA) copolymerization complexes, which consist of hydrogen passing between monomer units of complementary polymer chains.

Formed by bonding and plasticized with PEG-200, glycerol, or polypropylene glycol (PPG), the molecular weight of 425g/mo1(German patent application DE4219368).

There are intractable and conflicting technical requirements for the desired properties of adhesives intended for use on human skin and/or mucosal tissues.