bluuebunny/crossref_metadata_2025 huggingface dataset:
Mosaic deletion 11p13 in a child with dopamine beta‐hydroxylase deficiency—Case report and review of the literature
Authors: Erez A. , Li J. , Geraghty M.T. , Ben‐Shachar S. , Cooper M.L. , Mensing D.E. , Vonalt K.D. , Ou Z. , Pursley A.N. , Chinault A.C. , Patel A. , Cheung S.W. , Sahoo T.
Published: February 2010

Dopamine beta‐hydroxylase (DBH) deficiency is characterized by a lack of sympathetic noradrenergic function. Affected individuals exhibit profound deficits in autonomic regulation of cardiovascular function. The diagnosis of DBH deficiency is based on clinical findings, biochemical studies, and sequencing of DBH gene. We report here the characterization of a mosaic cytogenetic abnormality detected by array‐CGH in a 16‐year‐old female with primary DBH deficiency together with dysmorphic features. These features could not be explained by DBH deficiency leading to further investigation. Karyotype was reported normal (46,XX), while a targeted genomic array‐CGH revealed a mosaic loss for a segment of at least 1 Mb across 11p13. This segmental loss included the PAX6 and WT1 genes within the WAGR syndrome critical region. Interestingly, the derivative chromosome 11 was observed only in about 28% of cells analyzed. Utilizing a genome‐wide oligonucleotide‐based array, the deletion segment was estimated to encompass a segment of ∼10 Mb. Mosaic deletions of 11p13 in WAGR are extremely uncommon. In this case it is distinctly possible that the patient's bilateral iris colobomata might be a manifestation, albeit abbreviated, of the haploinsufficiency for PAX6. This case highlights the importance of cytogenetic analysis when a mutation alone cannot account for the complete phenotype. It also emphasizes the enhanced ability of high‐resolution array‐CGH techniques in accurately detecting subtle rearrangements in a mosaic form. Finally, it demonstrates the possible phenotypic effects of low‐level PAX6 haploinsufficiency in a dosage‐sensitive manner. © 2010 Wiley‐Liss, Inc.
Monozygotic twins discordant for neurofibromatosis 1
Authors: Kaplan Lee , Foster Rosemary , Shen Yiping , Parry Dilys M. , McMaster Mary L. , O'Leary Melanie Collins , Gusella James F.
Published: February 2010

We present monozygotic twins discordant for the autosomal dominant disorder neurofibromatosis type 1 (NF1). The affected twin was diagnosed with NF1 at age 12, based upon accepted clinical criteria for the disorder. Both twins were re‐examined at ages 35 and 57, at which times the unaffected twin continued to show no clinical manifestations of NF1. Short tandem repeat marker (STR) genotyping at 10 loci on chromosome 17 and 10 additional loci dispersed across the genome revealed identical genotypes for the twins, confirming their monozygosity. The affected twin has three children, two of whom also have NF1, while the unaffected twin has two children, both unaffected. Using lymphoblastoid, fibroblast, and buccal cell samples collected from both twins and from other family members in three generations, we discovered a pathogenic nonsense mutation in exon 40 of the NF1 gene. This mutation was found in all cell samples from the affected twin and her affected daughter, and in lymphoblastoid and buccal cells but not fibroblasts from the unaffected twin. We also found a novel non‐synonymous change in exon 16 of the NF1 gene that was transmitted from the unaffected mother to both twins and co‐segregated with the pathogenic mutation in the ensuing generation. All cells from the twins were heterozygous for this apparent exon 16 polymorphism and for single nucleotide polymorphisms (SNPs) within 2.5 kb flanking the site of the exon 40 nonsense mutation. This suggests that the NF1 gene of the unaffected twin differed in the respective lymphoblastoid cells and fibroblasts only at the mutation site itself, making post‐zygotic mutation leading to mosaicism the most likely mechanism of phenotypic discordance. Although the unaffected twin is a mosaic, the distribution of the mutant allele among different cells and tissues appears to be insufficient to cause overt clinical manifestations of NF1. © 2010 Wiley‐Liss, Inc.
c. 595‐596 insC of FOXC2 underlies lymphedema, distichiasis, ptosis, ankyloglossia, and Robin sequence in a Thai patient
Authors: Tanpaiboon Pranoot , Kantaputra Piranit , Wejathikul Karn , Piyamongkol Wirawit
Published: February 2010

Lymphedema–distichiasis syndrome is a rare primary lymphedema inherited as an autosomal dominant disorder. The characteristic features consist of late onset‐lymphedema and distichiasis together with other occasionally seen features including varicose vein, cleft palate, ptosis, and congenital heart diseases. FOXC2 is the gene found to be associated with this syndrome. We report here the first Thai patient who has characteristic features of this syndrome and the infrequently described features including ankyloglossia, and Robin sequence which consists of glossoptosis, cleft palate, and micrognathia. Mutation analysis of FOXC2 revealed c. 595‐596 insC. © 2010 Wiley‐Liss, Inc.
Postnatal growth retardation, facial dysmorphism, spondylocarpal synostosis, cardiac defect, and inner ear malformation (cardiospondylocarpofacial syndrome?)—A distinct syndrome?
Authors: Sousa Sérgio B. , Baujat Geneviéve , Abadie Véronique , Bonnet Damien , Sidi Daniel , Munnich Arnold , Krakow Deborah , Cormier‐Daire Valérie
Published: February 2010

We report on two unrelated cases born to nonconsanguineous parents with a similar clinical presentation: hypotonia since the neonatal period, severe failure to thrive, postnatal growth retardation, facial dysmorphism, congenital cardiac defects (septal defect and non progressive multiple valve dysplasia), shortened extremities, carpal/tarsal and extensive vertebral synostosis, delayed carpal bone age, deafness, and inner ear malformations. Presently, both patients present with normal psychomotor development. Additional abnormal findings include extra oral frenulum, nasal speech, and vesico‐ureteral reflux. Molecular analysis in one patient excluded the Noggin gene and Filamin B (FLNB) was excluded in the other patient. Although some features are similar to spondylocarpotarsal synostosis syndrome, the exclusion of FLNB and this constellation of findings suggest a new entity, closely similar to an autosomal dominant condition reported by Forney et al. 1966 in a unique family. Identification of similarly affected patients should aid in the further elucidation of this syndrome. © 2010 Wiley‐Liss, Inc.
Vici syndrome associated with sensorineural hearing loss and evidence of neuromuscular involvement on muscle biopsy
Authors: McClelland Verity , Cullup Thomas , Bodi Istvan , Ruddy Deborah , Buj‐Bello Anna , Biancalana Valerie , Boehm J. , Bitoun Marc , Miller Owen , Jan Wajanat , Menson Esse , Amaya Luis , Trounce John , Laporte Jocelyn , Mohammed Shehla , Sewry Caroline , Raiman Julian , Jungbluth Heinz
Published: February 2010

Vici syndrome is a rare, genetically unresolved congenital multisystem disorder comprising agenesis of the corpus callosum, cataracts, immunodeficiency, cardiomyopathy, and hypopigmentation. An associated neuromuscular phenotype has not previously been described in detail. We report on an infant with clinical features suggestive of Vici syndrome and additional sensorineural hearing loss. Muscle biopsy revealed several changes including markedly increased variability in fiber size, increased internal nuclei, and abnormalities on Gomori trichrome and oxidative stains, raising a wide differential diagnosis including neurogenic atrophy, centronuclear myopathy (CNM) or a metabolic (mitochondrial) cytopathy. Respiratory chain enzyme studies, however, were normal and sequencing of common CNM‐associated genes did not reveal any mutations. This case expands the clinical spectrum of Vici syndrome and indicates that muscle biopsy ought to be considered in infants presenting with suggestive clinical features. In addition, we suggest that Vici syndrome is considered in the differential diagnosis of infants presenting with congenital callosal agenesis and that additional investigation has to address the possibility of associated ocular, auditory, cardiac, and immunologic involvement when this radiologic finding is present. © 2010 Wiley‐Liss, Inc.
Magnetic resonance imaging of a unique mutation in a family with Pelizaeus–Merzbacher disease
Authors: Miller Elka , Widjaja Elysa , Nilsson Daniel , Yoon Grace , Banwell Brenda , Blaser Susan
Published: February 2010

Pelizaeus–Merzbacher disease (PMD) is a rare dysmyelination disorder, characterized by significant developmental delay, truncal hypotonia, spasticity, dysarthria, and nystagmus. Conventional magnetic resonance (MR) images demonstrate discordance of myelin maturation, while newer MR techniques, such as MR spectroscopy and diffusion tensor imaging, may be helpful in disease assessment. We report on a family of two young boys and their mother who share the same unusual 4‐bp deletion of the PLP1 gene: c51_54 del TTCC, causing truncation of the PLP1 in exon 2. The brain MRI appearances in this unique deletion, using newer MR imaging, are described. © 2010 Wiley‐Liss, Inc.
A rare case of trisomy 15pter‐q21.2 due to a de novo marker chromosome
Authors: Pacanaro Ade Nubia Xavier , Christofolini Denise Maria , Kulikowski Leslie Domenici , Belangero Sintia Iole Nogueira , da Silva Bellucco Fernanda Teixeira , Varela Monica C. , Koiffmann Celia P. , Yoshimoto Maisa , Squire Jeremy A. , Schiavon Adriana V. , Heck Benjamin , Melaragno Maria Isabel
Published: February 2010

Supernumerary marker chromosomes (sSMC) may or may not be associated with an abnormal phenotype, depending on the presence of euchromatin, on their chromosomal origin and whether they are inherited. Over 80% of sSMCs are derived from acrocentric chromosomes and half of them include the short arm of chromosome 15. Generally, they appear as bisatellited isodicentric marker chromosomes, most of them are symmetric. These chromosomes are normally originated de novo and are associated with mild to severe intellectual disability but not with physical abnormalities. We report on a patient with an SMC studied using classical and molecular cytogenetic procedures (G and C banding, NOR staining, painting and centromeric fluorescent in situ hybridization (FISH), BAC‐FISH, and SKY). The MLPA technique and DNA polymorphic markers were used in order to identify its parental origin. The marker chromosome, monosatellited and monocentric, was found to be derived from a maternal chromosome 15 and was defined as 15pter‐q21.2. This is the report of the largest de novo monosatellited 15q marker chromosome ever published presenting detailed cytogenetic and clinical data. It was associated with a phenotype including cardiac defect, absence of septum pellucidum, and dysplasia of the corpus callosum. © 2010 Wiley‐Liss, Inc.
Cold‐induced sweating syndrome with neonatal features of Crisponi syndrome: Longitudinal observation of a patient homozygous for a CRLF1 mutation
Authors: Yamazaki Masanori , Kosho Tomoki , Kawachi Shigeo , Mikoshiba Maiko , Takahashi Jun , Sano Rena , Oka Kenji , Yoshida Kunihiro , Watanabe Tomoharu , Kato Hiroyuki , Komatsu Mitsuhisa , Kawamura Rie , Wakui Keiko , Knappskog Per M. , Boman Helge , Fukushima Yoshimitsu
Published: February 2010

Cold‐induced sweating syndrome (CISS) is a rare autosomal recessive disorder caused by mutations in CRLF1 (cytokine receptor‐like factor 1), characterized by profuse sweating in cold environmental temperature and craniofacial and skeletal features. Mutations in CRLF1 also cause Crisponi syndrome (CS), characterized by neonatal‐onset paroxysmal muscular contractions as well as craniofacial and skeletal manifestations and abnormal functions of the autonomic nerve system. To date, it is an unresolved problem whether the two conditions are distinct clinical entities or a single clinical entity with variable expressions or with different presentations depending on the patients' age at diagnosis. We report on a 30‐year‐old Japanese woman with CISS and homozygous out‐of‐frame 23‐base deletion of CRLF1. In infancy, she did not show paroxysmal muscular contractions, but showed feeding difficulty, hyperthermia, and facial characteristics including thick and arched eyebrows, a short nose with anteverted nostrils, full cheeks, an inverted upper lip, and a small mouth, resembling those observed in CS. Profuse sweating was noticed at 3 years of age. Cold‐induced sweating was recognized in her elementary school days. In adolescence to adulthood, she showed a Marfanoid habitus with progressive kyphoscoliosis and craniofacial characteristics including dolichocephaly, a slender face with poor expression, a distinctive nose with hypoplastic nares, malar hypoplasia, prognathism, and a small mouth. This is the first report of detailed longitudinal observation of a patient with CRLF1 abnormalities, compatible with the notion that CISS and CS may be a single clinical entity. © 2010 Wiley‐Liss, Inc.
Novel ANKH mutation in a patient with sporadic craniometaphyseal dysplasia
Authors: Zajac Allison , Baek Seung‐Hak , Salhab Imad , Radecki Melissa A. , Kim Sukwha , Hakonarson Hakon , Nah Hyun‐Duck
Published: February 2010

Craniometaphyseal dysplasia is caused by mutations in ANKH (ankylosis, progressive homolog [mouse]) in the majority of cases, and all of the reported mutations are single amino acid changes. Genomic DNA from an affected patient, his biological parents, and a sibling was amplified and ANKH was sequenced. The affected patient had a complex heterozygous mutation in exon 7 (c.936T > C, c.938C > G, c.942_953delTGGTTGACGGAA), predicting p.Try290Gln and p.Trp292_Glu295del. We studied the effect of the predicted mutation on the subcellular distribution of ANKH protein. Immunofluorescent labeling of COS‐7 cells transduced with normal or mutant Ank (murine progressive ankylosis), showed that normal Ank localized to both the plasma membrane and cytoplasm, whereas mutant Ank was detected only in the cytoplasmic compartment. We propose that this craniometaphyseal dysplasia mutation causes a loss of ANKH protein expression and activity in the plasma membrane as a result of aberrant intracellular protein trafficking. © 2010 Wiley‐Liss, Inc.
Histology and synchrotron radiation‐based microtomography of the inner ear in a molecularly confirmed case of CHARGE syndrome
Authors: Glueckert Rudolf , Rask‐Andersen Helge , Sergi Consolato , Schmutzhard Joachim , Mueller Bert , Beckmann Felix , Rittinger Olaf , Hoefsloot Lies H. , Schrott‐Fischer Anneliese , Janecke Andreas R.
Published: February 2010

CHARGE (Coloboma of the iris or retina, heart defects, atresia of the choanae, retardation of growth and/or development, genital anomalies, ear anomalies) syndrome (OMIM #214800) affects about 1 in 10,000 children and is most often caused by chromodomain helicase DNA‐binding protein‐7 (CHD7) mutations. Inner ear defects and vestibular abnormalities are particularly common. Specifically, semicircular canal (SCC) hypoplasia/aplasia and the presence of a Mondini malformation can be considered pathognomonic in the context of congenital malformations of the CHARGE syndrome. We obtained a temporal bone (TB) of a patient with CHARGE syndrome who died from bacteremia at 3 months of age. The clinical diagnosis was confirmed in the patient by direct DNA sequencing and the detection of a de novo, truncating CHD7 mutation, c.6169dup (p.R2057fs). We assessed changes of the TB and the degree of neural preservation, which may influence the potential benefit of cochlear implantation. The TB was analyzed using synchrotron radiation‐based micro computed tomography, and by light microscopy. The vestibular partition consisted of a rudimentary vestibule with agenesis of the SCCs. The cochlea was hypoplastic with poor or deficient interscaling and shortened (Mondini dysplasia). The organ of Corti had near normal structure and innervation. Modiolus and Rosenthal's canal were hypoplastic with perikarya displaced along the axon bundles into the internal acoustic meatus, which may be explained by the arrest or limited migration and translocation of the cell nuclei into the cochlear tube during development. © 2010 Wiley‐Liss, Inc.
Molecular and phenotypic aspects of CHD7 mutation in CHARGE syndrome
Authors: Zentner Gabriel E. , Layman Wanda S. , Martin Donna M. , Scacheri Peter C.
Published: February 2010

CHARGE syndrome [coloboma of the eye, heart defects, atresia of the choanae, retardation of growth and/or development, genital and/or urinary abnormalities, and ear abnormalities (including deafness)] is a genetic disorder characterized by a specific and a recognizable pattern of anomalies. De novo mutations in the gene encoding chromodomain helicase DNA binding protein 7 (CHD7) are the major cause of CHARGE syndrome. Here, we review the clinical features of 379 CHARGE patients who tested positive or negative for mutations in CHD7. We found that CHARGE individuals with CHD7 mutations more commonly have ocular colobomas, temporal bone anomalies (semicircular canal hypoplasia/dysplasia), and facial nerve paralysis compared with mutation negative individuals. We also highlight recent genetic and genomic studies that have provided functional insights into CHD7 and the pathogenesis of CHARGE syndrome. © 2010 Wiley‐Liss, Inc.
Peptide‐Based Methods for the Preparation of Nanostructured Inorganic Materials
Authors: Chen Chun‐Long , Rosi Nathaniel L.
Published: February 2010

With their unique sequence‐specific self‐assembly and their substrate recognition properties, peptides play critical roles in controlling the biomineralization of inorganic nanostructures in natural systems and in directing the assembly of important soft matter. These attributes render them particularly useful molecules for the fabrication of new materials. Researchers from many scientific disciplines now use peptides to direct the synthesis of new inorganic nanostructures and the assembly of soft biomaterials. In this Review we describe the developments in this field and focus on the versatility of peptides and their ability to direct the composition and structure of new inorganic materials.
Preparation and catalytic application of poly 4‐vinylpyridine microspheres
Authors: Cao Li‐Jing , Wang Ge , Shi Lin , Yang Mu , Sun Dong‐Bai
Published: February 2010

Poly 4‐vinylpyridine (P4VP) microspheres between 170 and 728 nm were synthesized by Emulsifier‐Free Emulsion Polymerization. The monomer concentration, ionic strength, and initiator concentration affected the microsphere size and size distribution. The increasing monomer concentration led to the increase of microsphere size, whereas the size distribution of the resultant P4VP microspheres increased with the increasing ionic strength of the reaction systems. Mo(O2)2O·2DMF was successfully anchored onto the P4VP microspheres by ligand exchange, and the heterogeneous catalyst showed high‐catalytic activity for epoxidation of cis‐cyclooctene with environmentally friendly hydrogen peroxide. The size and morphology of the supported microspheres has important influence on the catalytic activity. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Thermophysical properties of CTBN and HTPB liquid rubber modified epoxy blends
Authors: Thomas R. , Boudenne A. , Ibos L. , Candau Y. , Thomas S.
Published: February 2010

Thermal conductivity and diffusivity of carboxyl‐terminated copolymer of polybutadiene and acrylonitrile (CTBN) and hydroxyl‐terminated polybutadiene (HTPB) liquid rubber‐ modified epoxy blends were investigated. A good agreement was observed between the calculated values of the specific heat estimated from thermal conductivity, diffusivity, and density measurements and the DSC results. Measurements of the thermal conductivity values of HTPB/Epoxy blends were in good agreement with three simple theoretical models, which have been used thereafter for the estimation of the unknown value of the thermal conductivity of CTBN (kCTBN = 0.24 Wm−1K−1). The morphology of the rubber‐modified epoxy blends has been quantified and indicate a tendency towards co‐continuous phase upon the inclusion of higher weight percentage of rubber (≥30 wt %). Moreover, we notice a significant enhancement of the thermal conductivity during this morphological shift. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Crosslinking of polyvinyl alcohol (PVA) fibrous membranes with glutaraldehyde and PEG diacylchloride
Authors: Wang Yuhong , Hsieh You‐Lo
Published: February 2010

Polyvinyl alcohol (PVA) fibrous membranes were generated by elestrospinning 10% aqueous PVA solutions then rendered water insoluble by reactions with difunctional reagents. The as‐electrospun PVA fibers were semi‐crystalline as evident by melting behavior (Tm = 190°C ΔHm = 39 J/g) and wide angle x‐ray diffraction (peak at 2θ = 20°). Chemical reactions with glutaraldehyde in either aqueous sodium sulfate (GA/Na2SO4) or ethanol (GA/EtOH) and polyethylene glycol (PEG) diacylchloride in 1 : 1 (v:v) toluene/pyridine produced crosslinked PVA with varied effects on the crystalline structure of the fibers. The fiber diameters remained in the submicrometer range. Among all crosslinking agents and conditions studied, reaction with shorter PEG at lower extent produced water‐insoluble PVA fibrous membrane with least change to the interfiber porous structure. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Optimization of adhesion properties of polypropylene by surface modification using acrylic acid photografting
Authors: Balart J. , Fombuena V. , Balart R. , España J. M. , Fenollar R. Navarro, O.
Published: February 2010

Polypropylene is one of the most widely used plastic materials because of an excellent balance between properties, processability, and cost. Nevertheless, polypropylene is characterized by very low surface energy, and this has a negative effect on adhesion properties. The use of polypropylene in technological applications requires, in many cases, a surface pretreatment to modify surface activity, thus enhancing good adhesion levels. In this work, we have used photopolymerization of acrylic acid (AA) monomer on polypropylene surface by using UV radiation. This enables photografting of AA (highly polar) on polypropylene topmost layers, thus having a positive effect on overall surface activity of polypropylene surface and, consequently, adhesion properties can be remarkably improved. We have evaluated the influence of the exposure time to UV radiation on wettability changes and adhesion properties. Wettability changes have been studied by contact angle measurements and subsequent surface energy calculation. Chemical changes produced by photopolymerization of AA have been followed by Fourier transformed infrared spectroscopy. Mechanical characterization of adhesion joints has been carried out in two different ways: peel and shear. Fractured surface of adhesion joints has been characterized by scanning electron microscopy. The overall results show a remarkable increase in mechanical properties of adhesion joints for exposure times of about 180 s, which represents an interesting time from an industrial point of view. Therefore, photopolymerization process is highly useful to increase adhesion properties of polypropylene. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Amphiphilic silicone copolymers for pressure sensitive adhesive applications
Authors: Mecham Sue , Sentman Alan , Sambasivam Mahesh
Published: February 2010

Amphiphilic copolymers of poly(dimethylsiloxane)‐poly(maleic anhydride‐vinyl ethyl ether) (PDMS/MA/VEE) were synthesized using a polydimethylsiloxane macroinitiator. The effect of these copolymers in the properties of a silicone pressure sensitive adhesive was evaluated. The addition of the copolymers resulted in lower peel strength (more than 50% reduction) from stainless steel panel while the moisture vapor transmission rate (MVTR) showed a significant increase (8× times higher) compared to the neat pressure sensitive adhesive. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Poly(dimethylsiloxane‐b‐styrene) diblock copolymers prepared by reversible addition–fragmentation chain‐transfer polymerization: Synthesis and characterization
Authors: Guan Cheng‐Mei , Luo Zheng‐Hong , Tang Pei‐Ping
Published: February 2010

Well‐defined poly(dimethylsiloxane‐b‐styrene) diblock copolymers were prepared by reversible addition–fragmentation chain‐transfer (RAFT) polymerization. Monohydroxyl‐terminated polydimethylsiloxane was modified to form a functional polydimethylsiloxane/macro‐RAFT agent, which was reacted with styrene to form the diblock copolymers. The chemical compositions and structures of the copolymers were characterized by proton nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, and gel permeation chromatography. The surface properties and morphology of the copolymers were investigated with static water contact‐angle measurements, X‐ray photoelectron spectroscopy, transmission electron microscopy, and atomic force microscopy, which showed a low surface energy and microphase separation surfaces that were composed of hydrophobic domains from polydimethylsiloxane segments. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of the grain size of nanoparticle dye‐coated titanium dioxide on the short‐circuit current density and open‐circuit voltage of an indium tin oxide/titanium dioxide/poly(acrylonitrile)–propylene carbonate–lithium perchlorate/graphite solar cell
Authors: Rika  , Rahman M. Y. A. , Salleh M. M. , Umar A. A. , Ahmad A.
Published: February 2010

A dye‐sensitized indium tin oxide (ITO)/titanium dioxide (TiO2)/polyacrylonitrile (PAN)–propylene carbonate (PC)–lithium perchlorate (LiClO4)/graphite solar cell was fabricated, and its performance was tested in the dark and under the illumination of a 100 mW/cm2 light. Three TiO2 samples were used in the device, namely, uncoated TiO2, a TiO2 film coated with methyl red dye, and a TiO2 film coated with coumarin dye. The films were deposited onto an ITO‐covered glass substrate by a controlled hydrolysis technique assisted with a spin‐coating technique. The films were characterized by scanning electron microscopy to determine their average grain size. The smallest grain size (48 nm) was obtained for the uncoated film. An electrolyte of PAN–LiClO4 with PC plasticizer was prepared by a solution‐casting technique. A graphite electrode was prepared on a glass slide by an electron‐beam evaporation technique. The device showed rectification properties in the dark and showed a photovoltaic effect under illumination. The device with the uncoated TiO2 film showed the highest short‐circuit current density (2.0 μA/cm2) and an open‐circuit voltage of 0.64 V because it possessed the smallest grain size. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Synthesis and properties of poly(trimethylene terephthalate‐co‐2‐methyl‐ethylene terephthalate) random copolyesters
Authors: Wu Fangjuan , Yang Guisheng
Published: February 2010

Poly(trimethylene terephthalate‐co‐2‐methyl‐ ethylene terephthalate) random copolymers of various compositions were synthesized via traditional two‐step polycondensation by incorporating of 1,2‐propanediol. The molar composition of trimethylene terephthalate and 2‐methyl‐ethylene terephthalate units and chemical structure were confirmed by means of 1H‐NMR and Fourier transform infrared. The thermal properties of the copolyesters were evaluated by DSC and TGA. As far as the thermal properties is concerned, the main effect of incorporation of 1,2‐propanediol was a lowering in the melting temperature, and an increment of glass transition temperature compared to homopolymer PTT. Due to the effect of the lateral methyl groups in the polymeric chain, the thermal stability is slightly decreased as the amount of the MET units is increased. Furthermore, the crystals of PTT/MET copolyesters were observed by hot‐stage optical polarizing microscopy at the indicated crystallization temperatures. As expected, the incorporation of MET units in the polymer chain of PTT was found to decrease the dimension of the crystals. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Chelation ion‐exchange study of copolymer resin derived from 8‐hydroxyquinoline 5‐sulphonic acid, oxamide, and formaldehyde
Authors: Singru R. N. , Gurnule W. B.
Published: February 2010

Copolymers (8‐HQ5‐SAOF) were synthesized by the condensation of 8‐hydroxyquinoline 5‐sulphonic acid (8‐HQ5‐SA) and oxamide (O) with formaldehyde (F) in the presence of acid catalyst. Four different copolymers were synthesized by using varied molar proportion of the reacting monomers. Copolymer resin composition has been determined on the basis of their elemental analysis and average molecular weights of these resins were determined by conductometric titration in nonaqueous medium. Viscometric measurement in dimethyl sulphoxide (DMSO) has been carried out with a view to ascertain the characteristic functions and constants. Electronic spectra, FTIR, and proton nuclear magnetic resonance spectra were studied to elucidate the structures. The newly synthesized copolymer proved to be a selective chelating ion‐exchange copolymer for certain metals. The chelating ion‐exchange properties of this synthesized copolymer was studied for different metal ions such as Fe3+, Cu2+, Ni2+, Co2+, Zn2+, Cd2+, and Pb2+. A batch equilibrium method was used in the study of the selectivity of metal ion uptake involving the measurements of the distribution of a given metal ion between the copolymer sample and a solution containing the metal ion only for representative copolymer 8‐HQ5‐SAOF‐I due to economy of space. The study was carried out over a wide pH range, shaking time, and in media of various ionic strengths. The copolymer showed a higher selectivity for Fe3+, Cu2+, and Ni2+ ions than for Co2+, Zn2+, Cd2+, and Pb2+ ions. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Warpage of a large‐sized orthogonal stiffened plate produced by injection molding and injection compression molding
Authors: Lee Sung Hee , Kim Seong Yun , Youn Jae Ryoun , Kim Baek Jin
Published: February 2010

Rectangular plates of the size of 1800 × 600 × 12 mm3 and 1200 × 600 × 12 mm3 were selected for injection molding and injection compression molding, respectively, in order to investigate warpage characteristics of the large‐sized polymer plates with orthogonal stiffener. To determine the mold system and to reduce warpage of the specimen, numerical analyses for injection molding and injection compression molding were performed by using a commercial simulation code. Experiments were performed to verify the suggested mold system and warpage of the specimen. Relatively large warpage of the injection molded product was observed and small warpage of the injection compression molded product was generated. Compression force of the injection compression molding was only 6% of the clamp force of the injection molding. Warpage of the product was reduced significantly by using the injection compression molding. The injection compression molding will be used to substitute expensive and disused wood forms with inexpensive and recyclable polymer plates for concrete casting. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Synthesis of hydroxyethylcellulose‐graft‐poly(N, N‐dimethylacrylamide) copolymer by ATRP and as dynamic coating in capillary electrophoresis
Authors: Yang Runmiao , Liu Yuhai , Zheng Chunzhi
Published: February 2010

Hydroxyethylcellulose‐graft‐poly (N, N‐dimethylacrylamide) was synthesized by successive atom transfer radical polymerization (ATRP) of N,N‐dimethylacrylamide (DMA) monomer using HEC‐Br as initiator, CuBr and 5,5,7,12,12,14‐hexamethyl‐1,4,8,11‐tetraazamacrocyclotetradecane (Me6[14]aneN4) as catalyst and ligand, with molar ratio DMA: HEC‐Br (CBr): CuBr: Me6[14]aneN4 = 100 : 1 : 1 : 3. HEC–Br macroinitiator was synthesized by esterification of HEC with 2‐bromoisobutyryl bromide. GPC and 1H NMR studies show that the molecular weight of the resulting PDMA increased linearly with the conversion. Within 6 h, the polymerization can reach almost 60% of conversion. The copolymer is applied for the separation of basic proteins in capillary electrophoresis. The results show that this medium has a powerful capability in resisting basic proteins adsorption because the polymer forms noncovalent coating in silica capillaries. With a broad range of pH 2–7, proteins were separated with sufficient efficiencies above 200,000 plates/m. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Viscoelastic properties of nitrile rubber filled with lignite fly ash
Authors: Nillawong Manuchet , Sombatsompop Narongrit , Sirisinha Chakrit
Published: February 2010

Nitrile rubber (NBR) compounds containing various loadings of fly ash (FA) were prepared, and their viscoelastic properties and reinforcement mechanism were investigated and compared with those of natural rubber (NR) compounds reported previously. The results obtained exhibit an increase in storage modulus (G′) with increasing FA particularly at high FA loading. By contrast, the broadness of linear viscoelastic (LVE) region is found to decrease. With the use of Guth‐Gold equation, the positive deviation of experimental values of relative modulus outward the theoretical values is observed at low strain of deformation. However, at high deformation strain, the negative deviation is found. The results imply that the presence of pseudo‐network (as formed via FA–FA and FA–NBR interactions) and the ball bearing effect provided by FA having spherical shape are responsible for the reinforcement in FA filled NBR compounds. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Influence of water content, time, and temperature on the rheological behavior of polyethylene terephtalate
Authors: Souza A. M. C. , Leprêtre D. S. , Demarquette N. R. , Lacrampe M. F. , Krawczak P.
Published: February 2010

In this work, the main factors affecting the rheological behavior of polyethylene terephtalate (PET) in the linear viscoelastic regime (water content, time delay before test, duration of experiment, and temperature) were accessed. Small amplitude oscillatory shear tests were performed after different time delays ranging from 300 to 5000 s for samples with water contents ranging from 0.02 to 0.45 wt %. Time sweep tests were carried out for different durations to explain the changes undergone by PET before and during small amplitude oscillatory shear measurements. Immediately after the time sweep tests, the PET samples were removed from the rheometer, analyzed by differential scanning calorimetry and their molar mass was obtained by viscometry analysis. It was shown that for all the samples, the delay before test and residence time within the rheometer (i.e. duration of experiment) result in structural changes of the PET samples, such as increase or decrease of molar mass, broadening of molar mass distribution, and branching phenomena. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Sulphonation of polystyrene‐butadiene rubber with chlorosulphonic acid for proton exchange membrane: Kinetic study
Authors: Idibie C. A. , Abdulkareem A. S. , Pienaar H. C. vZ. , Iyuke S. E. , vanDyk L.
Published: February 2010

Proton exchange membrane for fuel cell application was synthesized from a hydrophobic polystyrene‐butadiene rubber (PSBR) via sulphonation at different temperatures (22, 35, 55, 65, and 75°C) and varying time with chlorosulphonic acid. Infra‐red spectroscopy (IR) and proton nuclear magnetic resonance (1H‐NMR) were used to confirm the occurrence of sulphonation. Sulphonation occurred only on the phenyl ring with a maximum degree of sulphonation of 70.96 mole percent. Consequently, 10−3–10−2S/cm proton conductivity was achieved. Two models for the reaction kinetics were investigated: first‐order reversible and first‐order irreversible, respectively. However, the reaction kinetic was found to obey the first‐order reversible model. The activation energy (Ea) of the reaction was calculated to be 41.56 kJ/mol of PSBR repeat unit, which is an indication that the reaction is nonspontaneous. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Polyurethane powder coatings crosslinked with allophanate structures containing polyisocyanates
Authors: Pilch‐Pitera Barbara
Published: February 2010

With the use of alicyclic diisocyanates, aliphatic alcohols and dibutyltin dilaurate as well as triethylamine as a catalysts internally‐blocked polyisocyanate crosslinkers which contained allophanate bonds were synthesized. The chemical structure of those compounds were characterized by IR, 1H‐NMR, and 13C‐NMR spectroscopy. Their molecular weight distribution (MWD) parameters were determined by gel permeation chromatography (GPC). Those blocked polyisocyanates were used for the production of ecological lacquer compositions and coatings. The unblocking and curing reactions were investigated on the DTA, TG, and DSC thermograms. The resulting powder lacquers exhibit an excellent appearance; they are transparent, smooth, and nonyellowing. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Hydrophobic modification of dickite and salt spray test study on LLDPE/modified dickite composite
Authors: Xue Bing , Jiang Yinshan , Li Fangfei , Xia Maosheng , Sun Mengmeng , Liu Darui , Zhang Xuguang , Yu Lixin
Published: February 2010

Dickite particles were modified by silane coupling agent, hexadecyl phosphate, oleic acid, and stearic acid (SA), respectively. Modified dickite was composed with linear low‐density polyethylene (LLDPE) to prepare a series of LLDPE/modified dickite composites. Hydrophilicity of modified dickite was characterized by dispersion experiments and contact angle tests. The results indicated that hydrophilicity of modified dickite decreases sharply, compared with nonmodified dickite. Among four modifying agents, SA had obvious effect on hydrophobic modification of dickite. Fourier‐transform infrared spectra results suggested that chemical bonding between modifying agent and dickite was beneficial to the hydrophobic modification. Results of salt spray tests illustrated that the introduction of modified dickite into LLDPE improved the anticorrosion properties of the polymer universally. The anticorrosion mechanism of LLDPE/modified dickite was analyzed by scanning electron microscope micrograph. The mechanical properties of the resultant composites displayed a fact of reinforcement of modified dickite. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation of chitosan films mixed with superabsorbent polymer and evaluation of its haemostatic and antibacterial activities
Authors: El‐Mekawy Ahmed , Hudson Samuel , El‐Baz Ashraf , Hamza Hanafy , El‐Halafawy Khalil
Published: February 2010

Blended and layered films were developed from chitosan and starch–poly (sodium acrylate‐co‐acrylamide) superabsorbant polymer (SAP) and were tested for haemostasis. The tensile properties of the films are reported. A simple in vitro test was used to peer rank the effect of the films on the ability of chitosan to aggregate blood cells. It was clear that the addition of SAP material to chitosan enhanced the ability of the resulted films to coagulate blood. When chitosan and SAP were blended with a ratio of 1 : 1 (v/v) using concentrations of 1–2% and 0.25–0.5% (v/v) of chitosan and SAP respectively, the resulted films reduced the erythrocyte sedimentation rate (ESR) by 22% as compared to the control, whereas the chitosan and SAP control films reduced ESR by 11% and 22% respectively. Also, the two layered films with 2% (v/v) chitosan exhibited the same percent of reduction. These haemostatic films were further investigated by FTIR, TGA, tensile, antimicrobial ability, and cytotoxicity. Some new peaks were observed by FTIR due to possible interaction between the OH groups of the starch and NH3+ groups of the chitosan. Also, the films showed good mechanical and thermal properties. Moreover, the films also expressed antibacterial activity against Pseudomonas aeruginosa with a bacterial reduction of 99%. All the film samples exhibited a viability percentage around 100% with no cytotoxic effect on the cells. Chitosan–SAP films can be described as biofilms with a homogeneous matrix, stable structure, and interesting mechanical properties, with possibilities of utilization in haemostasis. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Light‐control birefringence of oriented poly(vinyl cinnamate) by UV irradiation
Authors: Dong Xiaoming , Guo Jinbao , Jiao Yang , Wei Jie
Published: February 2010

The research focused on realizing the birefringence of light‐control polymer films. The photoelastic birefringence exhibits when Poly (vinyl cinnamate) (PVCi) films are stretched below their glass transition temperature (Tg). The birefringence of PVCi decreases when the UV irradiation happens because the side chains of the PVCi photo‐react when the oriented films are exposed to UV light. A method to quantify the birefringence ability of the polymer films is created and verified. Using this method, the decrease of the birefringence through the UV irradiation is quantified. The result shows the birefringence of PVCi can be controlled by altering the UV irradiation time. In addition, oriented PVCi films of different esterification degrees were prepared and irradiated at different time, and the birefringence of them was studied to clarify the birefringence mechanism of light‐control polymer films. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Experimental study of helium leakage parameters in flexible composite
Authors: Yao Xue Feng , Lei Yi Ming , Xiong Chao , Wang Xiao Qun , Wang Ya Qing
Published: February 2010

The helium leakage characterizations of flexible composites are experimentally studied in this article. Three data processing techniques (Defining method, Fourier series method, and Fast series method) are used to evaluate the helium leakage parameters including the diffusion coefficient D, the solubility S, and the permeant rate k. The chamber pressure variation for helium permeation in flexible composite is measured by the differential pressure method. The results indicate that Fast series method is an effective technology in extracting the helium leakage parameters for flexible composites. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Polymerization of methyl methacrylate in the presence of a nonpolar hydrocarbon solvent. I. Construction of a complete ternary phase diagram through an in situ polymerization
Authors: Jung Yunju , Luciani Carla Vanesa , Han Joong Jin , Choi Kyu Yong
Published: February 2010

This article presents the ternary phase diagram for methyl methacrylate (MMA), poly(methyl methacrylate) (PMMA), and n‐hexane system at 70°C. It was constructed by both theoretical calculations and online laser light scattering (LLS) technique. In situ polymerization of MMA in a nonpolar nonsolvent carried out in a LLS cell provides a new means for the accurate detection of the cloud points of highly viscous polymer mixtures, with polymer weight fractions over 0.6. The ternary phase diagram measured in this study can be used to design the reaction conditions for the precipitation and/or dispersion polymerization in a nonpolar nonsolvent medium where polymerization kinetics as well as polymer particle morphologies are strongly affected by thermodynamic phase separation phenomena. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of corona discharge on the morphology of polyester fiber top layer
Authors: Brzeziński Stefan , Tracz Adam , Połowiński Stefan , Kowalczyk Dorota
Published: February 2010

The penetration of a woven fabric by corona discharge is of paramount importance for the achievable result of its modification. It was examined how the fiber top layer structure of polyester woven fabric was changed because of its treatment with corona discharge under atmospheric pressure. The corona discharge used was generated with the use of an original generator equipped with a set of multisegmental electrodes that made it possible to obtain a required level of activation energy in successively supplied “portions,” which simultaneously prolonged the time of plasma impact. Changes in the topography of fiber top layer were examined by the AFM method. It has been found that this corona discharge can shape the fiber top layer in a qualitatively similar way as in the case of polyester films (characteristic globular structure). It has also been established that the achievable effect of modification is not limited exclusively to the fibers that form the external surface of the fabric activated, but it also affect, though to different extent, the fibers from various areas of the fabric structure. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Light‐weight polypropylene composites reinforced with whole chicken feathers
Authors: Reddy Narendra , Yang Yiqi
Published: February 2010

Light‐weight composites reinforced with whole chicken feathers have better flexural strength than composites reinforced with feather fibers (barbs) and nearly thrice higher tensile strength and seven times higher tensile modulus than composites reinforced with powdered chicken feather quill. Chicken feathers are not only inexpensive and abundantly available but also have unique properties such as low density and hollow centers that make them preferable as reinforcement materials, especially for light‐weight composites. However, the traditional methods of developing composites do not provide the flexibility of using feathers in their native form as reinforcement. So far, the components in feathers such as barbs or quills have been used separately and/or feathers have been mechanically processed to destroy their native form in order to use feathers as reinforcement in composites. A new method of making composites using nonwoven webs as matrix allows the incorporation of reinforcing materials in their native form such as whole chicken feathers to develop composites. This research shows that whole chicken feathers can be used as reinforcement in composites with better flexural, tensile, and acoustic properties than composites made from processed chicken feathers. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Poly(vinyl alcohol)–polyacrylamide blends with cesium salts of heteropolyacid as a polymer electrolyte for direct methanol fuel cell applications
Authors: Helen M. , Viswanathan B. , Murthy S. Srinivasa
Published: February 2010

A class of inorganic–organic hybrid membranes with low methanol permeability characteristics for possible direct methanol fuel cell (DMFC) applications was architected, formulated, and fabricated through the blending of poly(vinyl alcohol) (PVA) and polyacrylamide (PAM) followed by crosslinking with glutaraldehyde (Glu). Cesium salts of different heteropolyacids, including phosphomolybdic acid (PMA), phosphotungstic acid (PWA), and silicotungstic acid (SWA), were incorporated into the polymer network to form corresponding hybrid membrane materials, namely, PVA–PAM–CsPMA–Glu, PVA–PAM–CsPWA–Glu, and PVA–PAM–CsSWA–Glu, respectively (where “Cs” together with a heteropolyacid abbreviation indicates the cesium salt of that acid). All the three hybrid polymer membranes fabricated exhibited excellent swelling, thermal, oxidative, and additive stability properties with desired proton conductivities in the range 10−2 S/cm at 50% relative humidity. A dense network formation was achieved through the blending of PVA and PAM and by crosslinking with Glu, which led to an order of magnitude decrease in the methanol permeability compared to the state‐of‐the‐art commercial Nafion 115 membrane. The hybrid membrane containing CsSWA exhibited a very low methanol permeability (1.4 × 10−8 cm2/s) compared to other membranes containing cesium salt of heteropolyacids such as PMA and PWA. The feasibility of these hybrid membranes as proton‐conducting electrolytes in DMFC was investigated, and the preliminary results were compared with those of Nafion 115. The results illustrate the attractive features and suitability of the fabricated hybrid membranes as an electrolyte for DMFC applications. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010