Use of Natural Polymers

There are a number of factors that favor the use of natural polymers as a source for polymer production. The concerns of environmental pollution, tensions in the Persian Gulf countries regarding oil, the fear of a possible future depletion of oil, etc., give credence to the move toward a bio-based material policy [8,21]. The... 

Most of all, in daily life, shelter, clothing, food, education, and recreation depended, and still depend, essentially on the use of natural polymers—wood, cotton, fur, wool, silk, starch, leather, paper, rubber, and a variety of resins, glues, and coatings. Around each of these materials a highly sophisticated art developed—entirely empirical and without any basic knowledge and, in fact, in most cases, without any concern about the material s composition and structure. 

The use of natural polymers to make plastic products started as early as 1760, when Enoch Noyes opened a business making combs out of keratin and albuminoid organic proteins derived from animal horns and horse hoofs. However, the first commercially successful plastic material, celluloid, would not come about for another hundred years. 

Let us mention, finally, that there is also a growing number of works di-reeled to the use of natural polymers. such as albumin, gelatin, or casein (104), For instance, albumin microspheres can be prepared by denaturalization (by heat treatment, or by formaldehyde addition) of natural albumin. In addition to being useful in the exploration, for diagnostic purposes, of the reticuloendothelial sys-... 

As a partial solution to the global issue of plastic waste, in recent years much interest has been devoted to the formulation of environmentally degradable plastic materials. In particular the use of natural polymers presents several advantages such as biodegradability, utilizing of renewable resources, recyclability. At the same time water sensitivity and degradability of natural polymers limit their possible applications. Consequently bioplastics cannot replace synthetic plastics in every application but they can result appropriate in specific products especially for those applications in which recovery of plastics is not economically feasible, viable and... 

The adhesion to surfaces of natural materials, such as wood, textiles or skin products is often determined by the Hydrogen bonding forces, as is the cohesion of the adhesive itself. The uses of natural polymers are numerous, as exemplified by their occurrence in varnishes, paint binders, inks and sealants. There are many similarities between these materials and adhesives. Mixtures are not uncommon, and therefore inconsistent performance may be expected. The adhesives are then better described principally in relation to their use and not exclusively on their chemical, geographical or historic attributes. 

Sell SA, Wolfe PS, Garg K, McCool JM, Rodriguez lA, Bowlin GL. The use of natural polymers in tissue engineering a focus on electrospun extracellular matrix analogues. Polymers 2010 2 522-53. 

Surface topology Surface topology dictates cellular infiltration, adhesion, and differentiation. Considering the complex interactions between cells and the extracellular matrix (ECM), hiomimetic TE approaches are becoming increasingly popular. The use of natural polymer and the introduction of specific cell adhesion motifs in synthetic biomaterials have been demonstrated to improve cell adhesion, minimize immune response, and favor tissue-specific cell differentiation. ... 

Physical gelation Relative simple design use of natural polymers able to respond to in vivo stimuli Weak stability low mechanical properties lack of control upon injection 29,79,81,86,105... 

While the use of natural polymers dates back to the dawn of civilization, polymer science developed rather recently. Tables 14.11,14.12, and 14.13 delineate three distinct stages in the discovery, invention, and theory. The vulcanization of natural rubber and the synthesis of phenol-formaldehyde plastics... 

In another example, Mutalik et at. demonstrated the use of natural polymers in preparing co-crystals that improve the pharmacokinetics and pharmacodynamics in animal models. The biocompatibility and the biodegradability of these polymers provide an added advantage as co-crystal formers. In the... 

Historically, the earliest "man-made" bioactive polymeric systems utilized a natural polymer (or a modification) in some manner. The advent of the totally synthetic polymers is a more recent innovation. Like many things, however, this pattern appears to be cyclic and we are seeing a renewed interest in the use of natural polymers. This is due, in part, to the perceived need to use renewable resources and, in part, to the desire... 

There is a general move toward an inaeased use of natural polymers that are biocompatible, biodegradable, and nontoxic. 

Make use of natural polymers, which may be modified but remain intact to a large extent (e.g., starch polymers). 

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