A5001189346- Polymer crystallization and properties
- Polymer Nanocomposites and Properties
- biodegradable polymer synthesis and properties
- Organometallic Complex Synthesis and Catalysis
- Advanced Polymer Synthesis and Characterization
- Block Copolymer Self-Assembly
- Fiber-reinforced polymer composites
- Pancreatic and Hepatic Oncology Research
- Gallbladder and Bile Duct Disorders
- Esophageal and GI Pathology
- Gastric Cancer Management and Outcomes
- Biliary and Gastrointestinal Fistulas
- Gastrointestinal disorders and treatments
- Synthetic Organic Chemistry Methods
- Synthesis and properties of polymers
- Pediatric Hepatobiliary Diseases and Treatments
- Pancreatitis Pathology and Treatment
- Neuroendocrine Tumor Research Advances
- Surfactants and Colloidal Systems
- Carbon dioxide utilization in catalysis
- Natural Fiber Reinforced Composites
- Nanomaterials for catalytic reactions
- Conducting polymers and applications
- Diverticular Disease and Complications
- Hydrogels: synthesis, properties, applications
Humanitas Mater Domini
2019-2025
University of Naples Federico II
2015-2024
Humanitas University
2020-2024
Dutch Polymer Institute
2022-2023
NXP (Netherlands)
2020-2022
IRCCS Humanitas Research Hospital
2018-2020
Istituti di Ricovero e Cura a Carattere Scientifico
1993-2020
Istituto Nazionale di Fisica Nucleare, Sezione di Napoli
2003-2019
Angelo State University
2019
RELX Group (Netherlands)
2018
The structure of physical poly(vinyl alcohol) (PVA) hydrogels prepared by subjecting a PVA/D2O solution (11% w/w PVA) to freeze (−22 °C)/thaw (+25 °C) cycles has been systematically investigated X-ray powder diffraction technique as function the number and aging time. structural analysis extended PVA "dried gels" obtained rehydrating dried samples. results present confirm that highly stable hydrogels, with water uptake higher than 80%, may be upon freeze/thaw cycles. profiles have...
A series of MAO-activated C(1)-symmetric indenyl-ansa-dithienocyclopentadienyl-based zirconocenes have been used to produce isotactic polypropylenes medium high molecular weights, different degrees stereoregularity, and free from regioerrors. The effect the presence rr defects on polymorphic behavior mechanical properties polypropylene is analyzed. induces crystallization gamma form disordered modifications intermediate between alpha forms. linear relationship amount average length sequences...
The crystallinity of freeze/thaw poly(vinyl alcohol) (PVA) hydrogels, either fresh or aged obtained by dipping dried gel samples in water immediately after their preparation, was investigated using different techniques. Free induction decays from 1H NMR experiments provide the most accurate measurement degree these systems. Values thus are a good agreement with data X-ray diffraction for all under study. degrees crystallinity, determined differential scanning calorimetry (DSC), instead,...
We report the cocrystallization of regio- and stereoregular chiral copolymer poly(limonene carbonate). To best our knowledge, this marks first example an amorphous, enantiomerically pure polymer that becomes crystalline upon stereocomplexation with its complementary enantiomer. By analyzing X-ray powder diffraction data, we propose a packing model in which sheets enantiopure chains interdigitate layers opposite enantiomer, forming "steric zipper".
Age-long ambition of medical scientists has always been advancement in healthcare and therapeutic medicine. Biomedical research indeed claims paramount importance nanomedicine drug delivery, the development biocompatible storage structures for delivering drugs stands at heart emerging scientific works. The delivery into human body is nevertheless a nontrivial challenging task, it often addressed by using amphiphilic compounds as nanosized vehicles. Pluronics belong to peculiar class...
Background and aims Autoimmune pancreatitis (AIP) is an immune-mediated disease of the pancreas with distinct pathophysiology manifestations. Our were to characterize type 1 AIP in a large pan-European cohort study effectiveness current treatment regimens. Methods We retrospectively analyzed adults diagnosed since 2005 or not-otherwise-specified 42 European university hospitals. Type was uniformly using specific diagnostic criteria. Patients 2 those who had undergone pancreatic surgery...
A detailed analysis of the structure and thermal behavior samples isotactic polypropylene (iPP) prepared with a highly regiospecific metallocene catalysts is presented. The present variable amounts stereodefects (isolated rr triads) provide first example metallocene-made iPP not including regioirregularities. They crystallize from melt in mixtures α γ forms. content form increases increasing crystallization temperature, reaches maximum value, then decreases for further increase temperature....
Isotactic propylene−ethylene (iPPEt) and propylene−butene (iPPBu) copolymers have been prepared with different metallocene catalysts. The influences of stereodefects (isolated rr triads), ethylene butene comonomeric units on the crystallization α γ forms isotactic polypropylene (iPP) discriminated. Both iPPEt iPPBu crystallize from melt as mixtures forms. amount form increases increasing temperature, comonomer concentration, content stereodefects. In copolymers, decreases for concentration...
Abstract The solvent molecules included in the clathrates (δ‐form) of syndiotactic polystyrene (s‐PS) are removed by suitable extraction procedures. An emptied δ‐form is produced which different from known γ‐form obtained heating. structural changes induced thermal treatments on and filled s‐PS, have been followed thermogravimetry, X‐ray diffraction analysis, differential scanning calorimetry Fourier‐transform infrared spectroscopy. It shown that, under conditions, can be transformed into a...
A study of the crystallization from melt and polymorphic behavior isotactic poly(1-butene) (iPB) prepared with metallocene catalysts is presented. Samples polybutene different stereoregularity, containing concentrations stereodefects (rr triads defects) regiodefects (4,1 units) have been C2- C1-symmetric catalysts. The concentration defects molecular mass are controlled through a rational choice catalyst structure conditions polymerization. Highly samples rr lower than 2 mol %, crystallize...
Random copolymers of propylene with ethylene, butene, and hexene comonomers have been prepared different metallocene catalysts. The used catalysts allowed a precise control concentration stereodefects high degree comonomer incorporation while maintaining molecular mass random distribution comonomers. Incorporation produces great enhancement ductility, flexibility, toughness, as compared to highly isotactic polypropylene, but important differences in the values elastic modulus strength...
The polymorphic transformations associated with the plastic deformation of isotactic polypropylene samples different stereoregularity, prepared metallocene catalysts, have been studied. Crystals alpha or gamma forms, present in unstretched samples, transform into mesomorphic form by stretching. formation mesophase facilitates successive further up to very high strains and produces development outstanding unusual properties flexibility elasticity. phase diagram polypropylene, where regions...
The structural organization of matter in poly(vinyl alcohol) (PVA) hydrogels obtained by repeatedly freezing and thawing dilute solutions PVA D2O is investigated use small-angle neutron scattering measurements (SANS). This study the first systematic quantitative investigation medium range length scales on techniques. studied gels have a complex hierarchical structure, extending over wide scales. micron scale originates from presence two separated phases constituted polymer-rich polymer-poor...
A structural characterization of samples isotactic propylene−butene copolymers (iPPBu), synthesized with a metallocene catalyst, is reported. The crystallize in the entire range comonomer compositions, and α γ forms polypropylene (iPP) propene-rich copolymers, whereas form I polybutene (iPB) crystallizes butene-rich samples. Butene propene comonomeric units are included crystals iPP iPB, respectively, as indicated by change unit cell parameters copolymer changing composition. trigonal iPP,...
A study of the crystallization behavior and mechanical properties random isotactic butene–ethylene copolymers prepared with a metallocene catalyst is presented. The use catalysis ensures fine control over molecular structure low concentration rr stereodefects (0.8%), negligible amount regiodefects, uniform distribution ethylene constitutional defects. This characteristic has allowed evidencing only effect presence units on polymorphic polybutene (iPB). accelerates transition form II into I...
We report on the self-assembling of clusters gold-nanoparticles (Au-NPs) directed by phase separation poly(styrene)-b-poly(methylmethacrylate) (PS-b-PMMA) block-copolymer (BCP) indium tin oxide coated glass, which induces onset vertical lamellar domains. After thermal evaporation gold BCP, Au-NPs 4 nm are selectively included into PS-nanodomains annealing, and then clustered with large density hot spots (> 10(4) μm(2)) in a random two-dimensional pattern. The resulting nanostructure exhibits...
Extensive characterizations, mainly by wide-angle X-ray diffraction (WAXD) and Fourier transform infrared (FTIR) techniques, are reported for co-crystalline (CC) poly(2,6-dimethyl-1,4-phenylene)oxide (PPO) films with many different low-molecular-mass guest molecules. These characterizations also the corresponding nanoporous crystalline (NC) phases, as obtained suitable guest-removal procedures. Two well-separated NC forms, hereafter named α β, removal from two groups of CC forms. β forms can...
The structural characterization of samples syndiotactic polypropylene (s-PP) isothermally crystallized from the melt is presented. Form I s-PP, with variable amount disorder, obtained at every crystallization temperature. limit ordered modification, characterized by a fully antichiral packing along both axes unit cell and monoclinic symmetry P21/a, only high values temperature (Tc > 135 °C). At temperatures in range 120−135 °C, modifications disorder regular alternation left- right-handed...
A comparative analysis of the polymorphic behavior samples isotactic polypropylene (iPP) prepared with heterogeneous Ziegler−Natta catalysts and a single-center homogeneous metallocene catalyst is presented. Different iPP, MgCl2-supported modified by adding different Lewis bases, have been fractionated extraction boiling solvents. The irregular fraction, insoluble in diethyl ether soluble hexane, crystallizes from melt almost totally γ form. more stereoregular fractions crystallize instead...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMesomorphic form of syndiotactic polystyrene as composed small imperfect crystals the hexagonal (.alpha.) crystalline formFinizia Auriemma, Vittorio Petraccone, Francesco Dal Poggetto, Claudio De Rosa, Gaetano Guerra, Carla Manfredi, and Paolo CorradiniCite this: Macromolecules 1993, 26, 15, 3772–3777Publication Date (Print):July 1, 1993Publication History Published online1 May 2002Published inissue 1 July...
A study of the structure isotactic propylene−hexene random copolymers, prepared with single-center metallocene catalysts, is reported. For low concentrations hexene comonomeric units, up to nearly 10 mol %, copolymers crystallize in α form polypropylene. Copolymers contents higher than % a new polymorphic that melts at 50 °C. The units are partially included both crystals and form. crystallization crystalline allows incorporation high amount units. melting temperature crystallinity decrease...
A study of the morphology and mechanical properties mesomorphic form isotactic polypropylene (iPP) that crystallizes in samples different stereoregularity prepared with metallocene catalysts is reported. Highly slowly crystallized from melt α show typical lamellar organization spherulites. Bundle-like elongated crystalline entities needle-like crystals γ are instead observed for stereoirregular form. All crystallize by fast quenching at 0 °C form, regardless stereoregularity. Crystals always...