Cellulose hydroxypropyl

BP Hydroxypropylcellulose JP Hydroxypropylcellulose PhEur Hydroxypropylcellulosum USPNF Hydroxypropyl cellulose 

Cellulose, hydroxypropyl ether E463 hyprolose Klucel Methoceh, Nisso HPC oxypropylated cellulose. 

The PhEur 2005 and USPNF 23 describe hydroxypropyl cellulose as a partially substituted poly(hydroxypropyl) ether of cellulose. It may contain not more than 0.6% of silica or another suitable anticaking agent. Hydroxypropyl cellulose is commercially available in a number of different grades that have various solution viscosities. Molecular weight has a range of 50 000-1 250 000 see also Section 10. 

Hydroxypropyl cellulose is widely used in oral and topical pharmaceutical formulations see Table I. 

In oral products, hydroxypropyl cellulose is primarily used in tableting as a binder, film-coating, and extended-release-matrix former.Concentrations of hydroxypropyl cellulose of 2-6% w/w may be used as a binder in either wet-granulation or dry, direct-compression tableting processes. Concentrations of 15-35% w/w of hydroxypropyl cellulose may be used to produce tablets with an extended drug release. The release rate of a drug increases with decreasing viscosity of 

Therapeutic Function Topical protectant ophthalmic vehicle Chemicel Name Callulose 2-hydroxypropyl ether Common Name Hyprolose Structural Formula  

---

The derivatives are hydroxyethyl and hydroxypropyl cellulose. AH four derivatives find numerous appHcations and there are other reactants that can be added to ceUulose, including the mixed addition of reactants lea ding to adducts of commercial significance. In the commercial production of mixed ethers there are economic factors to consider that include the efficiency of adduct additions (ca 40%), waste product disposal, and the method of product recovery and drying on a commercial scale. The products produced by equation 2 require heat and produce NaCl, a corrosive by-product, with each mole of adduct added. These products are produced by a paste process and require corrosion-resistant production units. The oxirane additions (eq. 3) are exothermic, and with the explosive nature of the oxiranes, require a dispersion diluent in their synthesis (see Cellulose ethers). 

Hydroxypropyl cellulose Creatinol phosphate Creatinolfosfate m-Cresol... 

ACPA azobis(4-cyanopentanoic acid) AIBN azobis isobutyronitrile) BPO benzoyl peroxide DVB divinyl benzene, EGA 2-ethylcyano-acrylate HPC hydroxypropyl cellulose MMA methyl methacrylate PAAc polyacrylic acid PEI polyethyleneimine, PEO/PPO polyethylene oxide/polypyropylene oxide copolymer PVME polyvinylmethylether PVP polyvinylpyrrolidone K-30 DMSO dimethylsulfoxide PGA polyglutaraldehyde CMS chloromethylstyrene PMMA-g-OSA polymethylmethacrylate grafted oligostearic acid. 

Paine et al. [85] extensively studied the effect of solvent in the dispersion polymerization of styrene in the polar media. In their study, the dispersion polymerization of styrene was carried out by changing the dispersion medium. They used hydroxypropyl cellulose (HPC) as the stabilizer and its concentration was fixed to 1.5% within a series of -alcohols tried as the dispersion media. The particle size increased from only 2.0 /itm in methanol to about 8.3 /itm in pentanol, and then decreased back to 1 ixm in octadecanol. The particle size values plotted against the Hansen solubility parameters... 

Pregelatinized starch Hydroxypropyl cellulose Calcium phosphate... 

Some part of the cellulose fraction is redirected to make cellulose derivatives, such as cellulose acetate, methyl and ethyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose. These derivatives find multiple applications, for instance, as additives in current products (e.g., paints, lacquers) of chemical industry. Typically, the preparation of cellulose derivatives takes place as a two-phase reaction cellulose is pretreated, for example, with alkali, and a reagent is added to get the substitution. Usually no catalyst is needed [5]. 

Hydroxypropyl cellulose Poly(sodium styrene sulfonate)... 

The use of hydroxypropyl cellulose (HPC), a binder, has increased in recent years [50a -50c], This material has been shown to reduce the incidence of capping when compared with MCC, PVP, and starch [50a], In addition, low substituted grades of HPC can also be used as a filler/ binder [50b]. 

Suspension of water soluble solids in oil can be achieved by a variety of chemical additives. Chemical suspension additives that have been suggested include alkyl mercaptophosphonic acids(174), organophylic clay plus hydroxypropyl cellulose(175), polyols(176), aluminum stearate(177), organophylic clay plus surfactant(178-181), aluminum phosphate esters(182), and acrylate copolymers(183-184). 

The materials used in these type of films include lipids, polysaccharides, and proteins. Starch (Maizura and others 2007), methylcellulose (Olivas and others 2003), hydroxypropyl cellulose (Brindle and Krochta 2008), chitosan (No and others 2007), xanthan gum (Mei and others 2002), alginate or zein (Zapata and others 2008), and soy protein (Park and others 2001) have been used for edible coatings. 

Excipients Cellulose, disodium hydrogen phosphate, hydroxypropyl cellulose, hydroxypropyl methylcellulose, lactose, mannitol, sodium lauryl sulfate, etc. 

Excipients Calcium carbonate, candeUUa wax, croscarmeUose sodium, hydroxypropyl cellulose, lactose monohydrate, magnesium stearate, microcrystaUine cellulose, polysorbate 80, simethicone emulsion... 

In the 1980s, Machid and Nagai [41] evaluated spray dosage forms based on hydroxypropyl cellulose (HPC) for the delivery of beclomethasone to treat recurrent and multiple apthae. Previously a double-layered tablet of HPC and Carbopol 934P was introduced in the market for the treatment of apthous stomatitis [41]. 

Probably the most widely studied cellulose derivative is hydroxypropyl cellulose (HPC) as the HPC-H2O system is very tractable. Werbowyj and Gray s report on HPC mesophases (1) stimulated numerous fundamental investigations by Gray and coworkers (2.10.65m75.78-8Q.9Q.99.112-115.117.118.121-124). White and coworkers (42.68.77.81). Sixou and Navard and coworkers (76.82-88). 

Note Examples are potassium salts of unbranched alkanoic acids, lecithin, certain polyisocyanates, cellulose derivatives with side-chains, such as (2-hydroxypropyl)cellulose, and cyanobiphenyl derivatives of alkyl(triethyl)ammonium bromide. 

Dispersion polymerization involves an initially homogeneous system of monomer, organic solvent, initiator, and particle stabilizer (usually uncharged polymers such as poly(A-vinyl-pyrrolidinone) and hydroxypropyl cellulose). The system becomes heterogeneous on polymerization because the polymer is insoluble in the solvent. Polymer particles are stabilized by adsorption of the particle stabilizer [Yasuda et al., 2001], Polymerization proceeds in the polymer particles as they absorb monomer from the continuous phase. Dispersion polymerization usually yields polymer particles with sizes in between those obtained by emulsion and suspension polymerizations—about 1-10 pm in diameter. For the larger particle sizes, the reaction characteristics are the same as in suspension polymerization. For the smallest particle sizes, suspension polymerization may exhibit the compartmentalized kinetics of emulsion polymerization. 

Nowadays, the sieving matrices most employed in CSE are polymer solutions that under suitable conditions may form a transient mesh or sieving matrix that provide the size-based separation of charged biopolymers. The polymer solutions can be formulated with linear acrylamide and N-substituted acrylamide polymers, cellulose derivatives, polyethylene oxide, and its copolymers or with a variety of polymers, such as polyvinylpyrrolidone (PVP), polyethylene oxide (PEO), and hydroxypropyl cellulose(HPC), which do not necessitate the preventive coating of the capillary wall due to their ability to dynamically coat the inner surface of the capillary, resulting in suppressed EOE and sample interactions with the capillary wall. 

---