2-hydroxypropyl cellulose HPC

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... 

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]. 

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). 

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. 

For (a), hydroxypropyl cellulose (HPC) (6-8), poly(vinyl pyrrolidone) (PVP) (9,10), poly(acrylic acid) (PAA) (9), and poly(dimethyl siloxane) (PDMS) (11) are usually employed. Ober et al. reported that the copolymers of isobutylene/isoprene and various methacrylates, which have weak polarity, are appropriate stabilizers for... 

Fig. 7. Comparison of experimental phase boundary concentrations between the isotropic and biphasic regions for various liquid-crystalline polymer solutions with the scaled particle theory for wormlike hard spherocylinders. ( ) schizophyllan water [65] (A) poly y-benzyl L-glutamate) (PBLG)-dimethylformamide (DMF) [66-69] (A) PBLG-m-cresoI [70] ( ) PBLG-dioxane [71] (O) PBLG-methylene chloride [71] (o) po y(n-hexyl isocyanate) (PHICH°Iuene at 10,25,30,40 °C [64] (O) PHIC-dichloromethane (DCM) at 20 °C [64] (5) a po y(yne)-platinum polymer (PYPt)-tuchIoroethane (TCE) [33] ( ) (hydroxypropyl)-cellulose (HPC)-water [34] ( ) HPC-dimethylacetamide (DMAc) [34] (N) (acetoxypropyl) cellulose (APC)-dibutylphthalate (DBP) [35] ( ) cellulose triacetate (CTA)-trifluoroacetic acid [72]...

Recent studies in this laboratory on hydroxypropyl cellulose (HPC) blends with lignin (9,10) have indicated that the composite morphology and properties are extremely sensitive to the degree of miscibility between the two components. This paper summarizes the observations that have been made with particular regard to the development of high-strength composites. For experimental details, the reader is referred to the above referenced publications. 

Commonly used cellulose derivatives include hydroxypropyl cellulose (HPC), car-boxymethylcellulose, and hydroxyethyl cellulose (HEC). The choice amongst these cellulose derivatives is primarily based on the type of formulation (aqueous or... 

Alginates Hydroxypropyl cellulose (HPC) Poly aery late... 

Recently, 2-hydroxypropyl cellulose (HPC) was demonstrated to be a very suitable matrix for UV/Vis absorption study of photoyellowing of milled-wood lignin in the solid state [10] where clean kinetics of discolouration were established after different chemical treatments of the lignin in solution. This indicates the importance in the discolouration process of phenolic structures without carbonyl groups and conjugated double bonds. The present communication describes a similar photochemical study on quinones and hydroquinones incorporated in HPC films under comparative concentrations ( 6.5xl0"5 mol/g HPC). For comparison, we also use UV/Vis reflectance spectroscopy to examine the behaviour of these compounds adsorbed on filter paper after light-exposure. 

Liquid-crystalline solutions and melts of cellulosic polymers are often colored due to the selective reflection of visible fight, originating from the cholesteric helical periodicity. As a typical example, hydroxypropyl cellulose (HPC) is known to exhibit this optical property in aqueous solutions at polymer concentrations of 50-70 wt%. The aqueous solution system is also known to show an LCST-type of phase diagram and therefore becomes turbid at an elevated temperature [184]. 

There have been continuing works by Suto et al. [213-217] on the preparation of cholesteric solid films of hydroxypropyl cellulose (HPC) crosslinked preferably with glutaraldehyde. Coloring conditions [213,217], swelling [215, 216], and tensile-creep behavior [214] of the crosslinked HPC films were examined. Also, the permselectivity of O2/N2 gasses for such liquid-crystalline cellulosic films was reported to become greater than that for the corresponding amorphous ones [218]. 

Poly(hydroxypropyl cellulose) (HPC) Strongly hydrophilic High... 

Hydroxypropyl cellulose (HPC) Hydroxyethylcellulose (HEC) Methylcellulose (MC) Polvinyl alcohol (PVA) Polyacrylic acid (PAA) Poly (meth) acrylic acid ester (PMAA) Polyvinyl pyrrolidone (PVP) Polyethylene glycols (PEG) White wax... 

Columns of dextran have been prepared with a more elaborate procedure.13 It is claimed that the EOF has been eliminated and that columns are very stable under very harsh conditions, e.g., 0.05 M NaOH with 5% SDS or 1 M HC1. Cellulose-coated capillaries have been prepared by coupling 2-hydroxyethyl methacrylate (HEMA)-derivatized hydroxypropyl cellulose (HPC) to columns derivatized with 7-oct-l-enyltrimethoxysilane.The coating was stable for several weeks in the pH range from 2 to 10 and diminished the EOF, and it has been found useful for separation of peptides, glycoproteins, and derivatized oligosaccharides. 

Rhinocort is a commercially available mucoadhesive transnasal powder preparation of beclomethasone dipropionate with hydroxypropyl cellulose (HPC) as a gelforming drug carrier developed by Suzuki and Makino [49], The HPC has been shown to promote the absorption of low-molecular-weight drugs, but it was not that effective with a peptide drug salmon calcitonin. Microcrystalline cellulose has been shown to be effective for the promotion of absorption of calcitonin in humans, producing about 10% bioavailability with rapid absorption onset [49], In the study... 

Cellulose derivatives Chitosans Gelatin Sodium carboxymethylcellulose (NaCMC) Methylcellulose (MC) Hydroxypropyl methylcellulose (HPMC) Hydroxypropyl cellulose (HPC) Hydroxyethyl cellulose (HEC)... 

Threshold volume fractions observed for cellulose acetate (CA and CTA), ethyl cellulose (EC) and hydroxypropyl cellulose (HPC), each in various solvents, are presented in Table 3. The results depend to some extent on the solventThe data included are not exhaustive. Other cellulose esters exhibit mesomorphic behavior Chanzy et al. observed mesomorphic behavior in solutions of cellulose itself when dissolved in N-methylmorpholine N-oxide containing water at concentrations of cellulose in the range 20-55 % w/v, depending on the temperature, the water content of the solvent and the degree of polymerization of the cellulose. Solutions of cellulose in mixtures of trifluoroacetic acid with 1,2-dichloroethane or with chloroform are hkewise lyotropic at concentrations of 20% (w/v) and above according to Patel and Gilbert... 

Hydroxypropyl cellulose (HPC) Propoxylated cellulose C 0 CH2-CHCH3-OH c 0 c Substituted pyranose chain sequences... 

Nakamura et al. ° studied the adhesion of water-soluble and neutral polymers, hydroxypropyl cellulose (HPC), xanthan gum (XG), tamarind gum (TG), and polyvinyl alcohol (PVA) to nasal mucosa in vitro and in vivo. The polymers, mixed with a dye, were applied as powders to the nasal cavity of rabbits, and the remaining dye residue was determined at 2, 4, and 6 h after nasal instillation with a thin fiberscope. The polymer XG showed the longest residence time of the dye in the cavity, followed by TG, HPC, and PVA in decreasing order. For the mixture XG and XG-PVA (2 8), some residue of dye could still be observed 6h after administration. The order of adhesion of these polymers to agar plates in vitro agreed with that of their mucoadhesion in vivo. Ilium et al. introduced bioadhesive microspheres for nasal delivery of poorly absorbable drugs. Radiolabelled microspheres made from diethylaminoethyl (DEAE)-dextran, starch microspheres, and albumin microspheres were administered to human volunteers and appeared to be cleared significantly slower than solutions or... 

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