Cellulose poly

It may also be mentioned that a number of commercial polymers are produced by chemical modification of other polymers, either natural or synthetic. Examples are cellulose acetate from the naturally occurring polymer cellulose, poly(vinyl alcohol) from polyfvinyl acetate) and chlorosulphonated polyethylene (Hypalon) from polyethylene. 

Hydroxypropyl cellulose Poly(sodium styrene sulfonate)... 

Sodium carboxymethyl cellulose Poly(vinyl pryidine)... 

Similar increases in k with ultrasonic intensity have been found for other polymers such as polystyrene [44], poly(methyl methacrylate) [45], poly(dimethylsiloxane) [46], poly(ethyleneoxide), hydroxyethyl cellulose, poly(vinyl acetate), poly(acrylamide)... 

Nonwovens are widely utilized as separators for several types of batteries. Lightweight, wet laid nonwovens made from cellulose, poly (vinyl alcohol), and other fibers have achieved considerable success as separators for popular primary alkaline cells of various sizes. The key nonwoven attributes include consistently uniform basis weight, thickness, porosity and resistance to degradation by electrolytes. Nonwovens are also successfully employed as separators in NiCd s. 

Hydrazine gel compns contg fuel metals (such as Al, Mg, Be, etc), microdimensional fibers (such as glass, asbestos, cellulose or synthetic) and thickeners, such as polyacrylamide, Na CM-cellulose, hydroxyethyl-cellulose, poly(vinyl)aIc, poly(Me methacrylate). Thus a soft gel was prepd. It contained hydrazine 65.20, polyacrylamide 0.67, microglass fibers 0.80 Al powder 33 33%... 

Elastomers, prepared by free-radical initiated copolymerization of ethyl acrylate with cellulose to several hundred percent extent of grafting of poly (ethyl acrylate) onto cellulose, exhibited rubber-like behavior and second-order transition temperatures. Cellulose-poly (ethyl acrylate) elastomers had transition temperatures below —35°C, about — 20°C, and below 5°C when measured in ethyl acetate, dry air, and water, respectively (43, 44). 

The preparation of cellulose copolymers with vinyl monomers, which have functional groups that are hydrophilic in nature, has given textile products with improved soil release properties. For example, as shown in Figure 5, crosslinked cellulose-poly (methacrylic acid) copolymer fabrics exhibited both increased oily and aqueous soil release during washing compared with the crosslinked control fabrics. However, for oily soil, when softeners were added to the wash water, this improvement in soil release decreased. Crosslinked cellulose-poly (hydroxyethyl methacrylate) copolymer fabrics exhibited no improvement in oily soil release and only slight improvement in aqueous soil release compared... 

Table X. Effects of Degree of Polymerization of the Irradiated Cellulose and Extent of Grafting on the Elastic Recovery Properties of Fibrous Cellulose—Poly (ethyl acrylate) at 25°C...

I. Pinnau, Ultrathin Ethyl Cellulose/Poly(4-methyl pentene-1) Permselective Membranes, US Patent 4,871,378 (October 1989). 

A novel attempt was made to realize different IPN architectures in a composite system of cellulose/poly(AT-vinyl pyrrolidone-co-glycidyl methacrylate) (CELL/P(VP-co-GMA)) [73]. The copolymer-rich compositions (4-19 wt % CELL) were synthesized successfully via photopolymerization in the gel state of cellulose impregnated with a monomer mixture of VP and GMA, resulting in the development of a semi-IPN-like organization (Fig. 5a) within the copolymerized bulks. An additional treatment of the as-polymerized composites ([O]-series) with 50% formic acid or 3% sodium hydrox-... 

Leva- Leva- Vinyl idene Cellulose Poly-... 

The morphology of the fibrous cellulose graft copolymers depended on the method of initiation of free radical formation, experimental conditions during the copolymerization, chemical modification of the cellulose before reaction, and the type of monomer used (60). Variations in the shape of the fibrous cross section, in layering effects in the fiber, and in the location and distribution of the grafted copolymer in the fiber were observed by electron microscopy (61). Cotton cellulose—poly (acrylonitrile) copolymer was selected to show the possible variations in location and distribution of the grafted copolymer in the fiber. 

Also the diffusivity of water in polymers is highly dependent on the polymer-water interaction. When a polymer contains many hydrogen-bonding groups (cellulose, poly (vinyl alcohol), proteins, etc., and to a lesser extent synthetic polyamides) the diffusivity increases with the water content. This is explained by the strong localisation of the initially sorbed water over a limited number of sites, whereas at higher water contents the polymer... 

Several polymers were found to fit all or most of the above criteria and were used to prepare the carrier films. Many polymers have been used for this purpose, viz., ethyl cellulose, poly(y-benzyl glutamate), poly(vinyl acetate), cellulose acetate phthalate, and the copolymer of methyl vinyl ether with maleic anhydride. In addition to the base polymers, plasticizers were often needed to impart a suitable degree of flexibility. Plasticizers, which are found to be compatible with polymeric materials include, acetylated monoglycerides, esters of phthalic acid such as dibutyl tartarate, etc. An excipient was usually incorporated into the matrix of the carrier films. The excipients used were water-soluble materials, which are capable of creating channels in the polymer matrix and facilitate diffusion of the drug. PEGs of different molecular weights were used for this purpose. 

Poly(acryhc acid), poly(glutamic acid), CM-cellulose, poly(acryl amide)... 

Fig. 2 Effects of a buffer s (a) ionic strength and (b) pH on th adsorption of LPS by various aminated cellulose adsorbents. Th adsorption of LPS was determined using a batchwise methoc with 0.2 g of the wet adsorbent and 2 mL of a LPS (E. coIm 0111 B4, 1000 ng/mL) solution. Adsorbent and AEC oS adsorbent PEl-cellulose=poly(ethyleneimine)-i mmobi li zedE CeUufine-GC15 (AEC 1.2 meq/g) PL-cellulose=poly( -ly-i sine)-immobibzed CeUufine-GC15 (AEC 0.6 meq/g) DAH- cellulose=diaminohexane-immobibzed Cellufme-GC15 (AECig, 0.2 meq/g). of adsorbent 2 x 10 .

Hydrophilic contact lenses (such as Soflens) are made from crosslinked poly(2-hydrox-yethyl methacrylates). These have also been utilised as drug carriers. Conventional eye medication has been modified over the years through the addition to formulations of a variety of viscosity-enhancing agents, polymers such as hydroxypropylmethyl cellulose, poly(vinyl alcohol) and silicones. These all prolong contact of dmg with the cornea by... 

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