ITRM20070245A1 - RADIOOPAC ORGANIC INORGANIC HYBRID THAT INCLUDES AN INORGANIC BONE AND POLYMER - Google Patents

Description

Description of the invention entitled:

"Radiopaque organic-inorganic hybrid comprising an inorganic oxide and a polymer"

The present invention refers to hybrid materials, also known by the name of ceramers, to processes for their preparation, to their uses in various applications and to the materials that comprise them.

Background of the invention

Hybrid materials formed by organic and inorganic components connected by covalent bonds have been known for some time {YanO, S., et al. , Mater. Ski. Eng., C 1998, 6, 75-81). These materials are also known in the sector with the names of "ceramers" (CERAmics and polymers) and "ormocers" (from the English "ormocers": ORGanically MODified CE-RamicS).

These materials are studied and used for their valuable mechanical, thermal, electrical and magnetic properties, resulting from the combination of the properties of the individual components.

The properties of the hybrid are particularly interesting when the size of the inorganic component is nanometric. This circumstance gives the hybrid peculiar physical characteristics and new optical properties appear (Caseri, W., Macromol. Rapid Commun.

2000, 21, 705-722).

Some inorganic oxides are used for their radiopacity properties in the medical sector and in all those sectors where protection from environmental radiation is necessary.

In particular, in the health sector, the radiopacity characteristics of certain materials are used both for the purposes of protecting personnel exposed to X-rays (medical personnel and patients), and to make certain materials traceable, for example endoprostheses.

The problem of radiation protection is particularly acute, see in this regard US 2004 / 0041107AÌ.

While the shielding of environments from radiation is solved with adequate building engineering works, the problem of shielding people requires the examination of several elements.

In particular, people who are in contact with radioactive elements, for example in the field of nuclear medicine, or with X-ray sources, both in the field of diagnostics and in that of treatment, must have access to adequate protection tools.

For immediately understandable reasons, these people's clothing itself is the first and most practical barrier to radiation.

Radiopaque fabrics obtained in different ways are known. Generally, the radiopaque material is impregnated on the fabric with different finishing techniques. However, the results are not always acceptable and several problems arise for the expert in the sector with the task of providing a radiopaque fabric that has good wearability characteristics, i.e. that is not too rigid after finishing with the radiopaque material, gives a feeling comfortable, especially for transpiration, it maintains its radiopacity properties over time and following washing and sterilization treatments. This problem is particularly felt by surgeons who must be able to have the greatest freedom of movement and wear comfortable clothing, as well as by healthcare personnel in general, but also by patients who are subjected to therapies or diagnostic techniques based on high-energy radiation.

The aforementioned patent application US 2004 / 0041107A1 discloses a radiation attenuation system, which comprises a polymeric resin and a radiation attenuating material dispersed in the resin. The dispersion of the radiopaque material in the polymer occurs by coextrusion. Alternatively, the radiopaque material is mixed into the polymer matrix prior to extrusion. A similar technique is described in WO 2004/021811, which also describes a radiopaque finishing of the fabric by impregnation with an inorganic salt solution.

US patent 6,459,091 describes garments with radiation protection characteristics obtained by impregnating the fabric with a light radiopaque inorganic material (with respect to commonly used lead derivatives). Impregnation occurs by immersing the fabric in a solution of the radiopaque material in the presence of an additive (adhesive, fixative, emulsifier).

WO B9 / 00831 describes the forming of protective shields resistant to ionizing radiations obtained by mixing a polymeric matrix with a radiopaque filler and suitable additives.

US 7,083,644 discloses radiation resistant implantable textile prostheses (for sterilization purposes) and characterized by a particular naphthalene dicarboxylate polymer.

WO 03/093357 discloses a composition for coating of various medical materials having good adhesion to the substrate. The mixture is quite complex and comprises a hydrophilic polymer in aqueous solution, a colloidal metal oxide and a cross-linking agent. Radiopacity is obtained by adding suitable auxiliary agents to the mixture. The various applications of this mixture do not include clothing for radiation protection purposes.

Mixtures of polymers and radiopaque material are also described in US 7,196,023.

Finally, WO 2006/069007 describes compositions and processes for forming radiopaque polymeric articles by mixing radiopaque material with a powdered, pelletized polymer or a liquid solution, emulsion or suspension of the polymer in solvent or water. Articles of clothing for radiation protection purposes are also described. Better results can also be obtained with the use of nanomaterials. This paper provides three ways to incorporate the nanomaterial into the polymer blend: by direct mixing of the polymer and the nanomaterial, as discrete phases or in solution; or by in situ polymerization in the presence of the nanomaterial; or formation of the nanomaterial in the presence of the polymer, which acts as a surfactant in the formation of the nanoparticles, without however creating covalent bonds between the two phases. The application of the mixture on the fabrics is carried out by spraying, adhesion or application by coating.

The optimal radio-opaque material should be permanently fixed to the fabric, to avoid its dispersion into the environment (dusting effect) and to withstand washing and sterilization treatments where necessary. Furthermore, to ensure the breathability of the garment, it should not constitute a continuous covering layer that closes the pores of the fabric.

Patent EP 0 918 061 describes organic-inorganic hybrid polymers, in which the polymer is selected from aromatic polycarbonates and aromatic polyesters with the aim of providing hybrids whose polymeric part is hydrophobic and the resulting material has mechanical characteristics suitable for the fields of application which it is destined. Hybrid applications are in the plastics industry, particularly molded items, films, sealing agents and adhesives, overcoating binders, building materials, optical materials, medical materials, but there is no mention of a possible application to textiles. Furthermore, this patent also solves some problems connected to the process of preparation of hybrids deriving from the use of hydrophobic polymers.

Summary of the invention

It has now been found that an organic-inorganic hybrid, also called ceramer, formed by a polymeric organic part and an inorganic part satisfies the needs presented in the state of the art. In particular, this hybrid consists of a polymeric part which confers favorable mechanical characteristics, such as flexibility, and an inorganic part which confers the desired radiopacity characteristics and, when nanometric in size, confers transparency to visible light.

Surprisingly, the hybrid according to the present invention can be used in the finishing of fabrics for the packaging of textile articles to be used in cases where it is necessary to provide radiation protection to living subjects. The hybrid according to the present invention gives the fabric an optimal covering of each single fiber, thus respecting the structure of the fabric, which maintains its wearability and transpiration characteristics. Furthermore, the peculiar characteristics of the ceramer make it permanent to washing and sterilization treatments.

The present invention relates to an organic-inorganic hybrid consisting of 1) an inorganic oxide and 2) a polymer selected from an aliphatic polyester, aliphatic polyetherester, aliphatic polycarbonate, aliphatic polyetherecarbonate and a copolymer thereof. In said hybrid, the polymer and the inorganic oxide are linked by covalent bonds.

The hybrid according to the present invention offers several advantages, which will become evident in the detailed description of the invention.

The material provided by the present invention is able to combine the good workability, flexibility and low density of polymers with the hardness, rigidity and thermal and chemical stability of inorganic oxides. The new and interesting properties of these materials are due to the presence of inorganic domains of nanometric / micrometric dimensions connected to the organic phase by covalent bonds.

Conveniently, the hybrid of the present invention is suitable for use in sectors that require radiopaque materials, with the aim of providing adequate protection from radiation, or of making the object containing the object radiopaque, therefore traceable in the presence of a radioactive source. 'hybrid.

The hybrids of the present invention possess radiopaque and UV-blocking properties (attributable to the inorganic phase), as well as transparency to visible light, when the inorganic phase is in the nanometric domain. The hybrid, as pointed out above, has mechanical properties (flexibility, ductility), associated with the organic polymeric phase, completely different from those of the pure inorganic phase and gives the material characteristics much more suitable for use in the field of coating. surfaces, compared to the solutions currently available. The physical-mechanical properties of the hybrid can be modulated not only by varying the ratio between the organic and inorganic phase, but also by acting on the nature, microstructure and degree of polymerization of the polymeric component.

The presence of a covalent chemical bond between the phases guarantees "anchoring" to the inorganic particles which prevents an involuntary release. On the other hand, this can happen for example in biomedical devices whose radiopacity is conferred by heavy metal salts dispersed in the polymeric matrix, or in fabrics treated with traditional finishing systems during the washing phases.

A further advantage of the hybrid of the present invention is given by the ease of application when it is used as a coating. Furthermore, this hybrid coating has greater elasticity and flexibility than any purely inorganic coating. The excellent adhesion towards both metal and polymeric substrates associated with the ease of application represents a further improvement aspect, which allows its application in the covering of surfaces of various kinds. In formulations where both the organic and the inorganic phase have characteristics of biocompatibility, the hybrid can be advantageously used for the coating of endoprostheses, such as for example stents.

As will be evident in the detailed description, the type of hybrid provided by the invention allows to obtain a stable chemical anchoring of the coating on the substrate, in the case of substrates having reactive groups, and this is a highly desired aspect compared to simple deposition.

A further advantage of the hybrid of the present invention lies in the low cost of its components and in the particularly short synthesis and application times of the coating.

One application concerns the field of technical / smart fabrics. The invention can confer the properties illustrated above (radiopacity, transparency, UV filter) to fabrics and clothing by means of a simple 'finishing' procedure. The presence of the polymeric phase in the hybrid decreases the stiffening effect of the fabric due to the presence of the inorganic ceramic phase, which is however responsible for the functional properties, ensuring flexibility and pleasantness to the touch. The tissues produced in this way can be used in hospitals for all medical personnel who are exposed to ionizing radiation (X-rays). Not only, for example, staff who perform angioplasty operations, but also patients who are exposed to radiation, both for diagnostic and therapeutic purposes, find a benefit in wearing comfortable protective clothing. The invention in fact allows the production of protective clothing that is easy to fit and use.

The material is also proposed as a coating for endoprosthesis devices that require radiographic traceability. The coating in question is made up of polymers and metal oxides known to be accepted for use in the biomedical field and this allows us to propose their use for the coating, for example. to crown stents in place of the currently used noble metal (Au or Ta) coatings. Furthermore, the application of this surface coating does not alter the massive properties of the material, as happens when the material is made up of polymers mixed with radiopacifying additives (Barium salts, etc.).

The materials object of the patent have been produced by sol-gel technique starting from commercial products or producible by known methods, and have been characterized by DSC, TGA, FT-IR and UV-Vis spectroscopy, SEM.

The materials, both in the form of a plate (thickness 0.1-0.4 mm) and of coating on cotton fabric, were subjected to radiographic investigation (using a mammography instrument), obtaining clear radiographic images that demonstrate their radiopacity. .

The visible light transparency of the materials object of the invention is a consequence of the nanometric dimensions of the inorganic oxide particles.

The materials, in the form of a thin coating of a polyolefin substrate, were subjected to UV-Vis spectroscopy and demonstrated the ability of the hybrid to completely absorb ultraviolet radiation below threshold values between 320nm and 340nm, thus acting as a UV filter.

Therefore, an object of the present invention is an organic-inorganic hybrid consisting of 1) an inorganic oxide, 2) a polymer selected from aliphatic polyester, aliphatic polyetherester, aliphatic polycarbonate, aliphatic polyetherecarbonate and their copolymers, in which the oxide is the polymer are linked by covalent bond.

In particular, an organic-inorganic hybrid, as defined above, is an object of the present invention, in which the polymer is represented by the following formulas:

in which:

a is selected between 0,1,2,3,4 and 5;

b is chosen between 0 and 1;

c is selected between 0,1,2,3,4 and 5;

d is selected between 0,1,2,3,4 and 5;

and is selected from 0.1;

the various a, b, c, d and e being equal or different in the two blocks n and m;

Ri, R2, R3, R4, equal or different from each other, are H, (CH2) kCH3, in which k is chosen between 0,1,2,3,4 and 5, or R1 and R2 are linked together to form a cycloalkylene;

R5 is selected from a group - (CR6R7) 1-, where 1 is an integer between 1 and 20, where R6 and R7, the same or different, are hydrogen or a C1-C8 alkyl group, linear or branched, and a group - [(CR8R9} P-X] r- where R8 and R9, equal or different from each other, are hydrogen or a C1-C8 alkyl group, linear or branched and a group e X is chosen from 0, S and NH, where r is an integer between 1 and 100 and p is an integer between 1 and 10;

or :

m which

a is selected from 0, 1, 2, 3, 4 and 5;

b is chosen between 0 and 1;

c is selected from 0, 1, 2, 3, 4 and 5;

d is selected between 0,1,2,3,4 and 5;

e is chosen between 0 and 1;

f is selected between 0,1,2,3,4 and 5;

a and c being equal or different in the two portions of the molecule;

R1, R2, R3, Ri4R5, R6, R7, R8 equal or different from each other, are H, (CH2) kCH3, where k is selected between 0,1,2,3,4 and 5;

Another object of the present invention is a process for the preparation of the hybrid, as well as the hybrid obtainable from said process.

A further object of the present invention is a material comprising said hybrid, in particular a radiopaque and UV-absorbing material. The uses of said material are further objects of the invention, as well as articles which contain said material.

Still another object of the present invention is a composite comprising the above hybrid in association with other substances for specific uses. An example of such a composite is the combination of the hybrid of the present invention with silver salts to impart antibacterial properties. This composite finds interesting applications in the health field, where the combination of radiopaque and antibacterial properties may be desirable, for example in the case of fabrics for medical use or endoprostheses for diagnostic or therapeutic use.

The present invention will now be illustrated in detail also by means of examples and figures.

In the figures:

Figure 1: represents the FT-IR spectra of the PBG (solid line) and of the hybrid El-b (dashed line), described in Example 1;

Figure 2: represents the UV-Vis spectra of: a) polypropylene (film thickness 31μm;); b) PP-E1-a (coating thickness: 6μm); c) PP-El-b (coating thickness: 5μm); d) PP-E1-c (coating thickness: 4μm); e) solution of PBG in THF, as described in Example 1;

Figure 3: shows SEM images at different magnification (x100 and x1000, indicated in the figure) of the cotton fabric before (a and c) and after treatment with the hybrid of the present invention (b and d, sample Cot-E2-b).

Detailed description of the invention

The metal oxides which constitute the inorganic part of the hybrid according to the present invention are known in the field not only of hybrids but also as radiopacifying additives, as described for example in the patent references cited above.

In a first preferred embodiment of the invention, said inorganic oxide is selected from the transition metal oxides of the Periodic Table of the Elements and those of Group IV A. Preferably this oxide is selected from yttrium oxide, cerium oxide, tantalum oxide , hafnium oxide, molybdenum oxide and niobium oxide, more preferably, the oxide is selected from zirconium oxide (zirconia) and titanium oxide (titania).

These oxides give the hybrid containing them the desired radiopacity characteristics and the ability to absorb UV radiation, as well as the mechanical characteristics that are desirable in the case of applications other than radiation protection or radiotraceability.

The polymer used in the present invention is an aliphatic polyester, an aliphatic polyetherester, an aliphatic polycarbonate, an alithic polyetherecarbonate and their copolymers as defined in the previous formulas.

The polymer or copolymer used has a molecular weight Mn between 200 and 50000 Da and is dihydroxy terminated.

In a preferred embodiment of the invention, said polyester or aliphatic polyether ester is selected from the group consisting of polylactic acid, polyglycolic acid, polyhydroxybutyric acid, polycaprolactone, polydioxanone, polypivalolactone, polyethylene adipate, polybutylenadipate, polybutylene butyl acetylene glycolate, polybutylene glycolate, polyethylene glycolate, polyethylene glycolate, polyethylene glycolate , while said polycarbonate or aliphatic polyetherecarbonate is polyethylene carbonate, polythrimethylene carbonate, polyhexamethylene carbonate, poly (2,2-dimethyl) propylene carbonate, polycyclohexanecarbonate, poly (ethylene etherecarbonate), poly (propylene ether-carbonate).

In a more preferred embodiment of the invention, the hybrid is formed by one of the aforementioned polymers and titanium oxide (titania).

The process for the preparation of the hybrid of the present invention comprises the preparation of an inorganic oxide in the presence of the selected polymer.

The inorganic oxide is prepared according to the solgel method. This method is well known to those skilled in the art and does not require particular descriptions. By way of example, please refer to Sumio Sakka "Handbook of Sol-gel Science and Technology: Processing, Characterization, and Applications" Springler 2004 or the aforementioned EP 0918 061.

Generally, the process for preparing the hybrid of the present invention is described as follows.

The hybrid can be represented by the diagram below

According to the process of the present invention, an ablution of the polymer is added to a solution of an inorganic oxide precursor to give a hybrid precursor solution.

Preferably, the solvent of the polymer solution is the same solvent as the solution of the inorganic oxide precursor.

Conveniently, the solution of the precursor of the inorganic oxide preferably contains an acid, preferably an inorganic acid, for example hydrochloric acid or sulfuric acid.

In another embodiment, the hybrid precursor solution may contain a certain amount of water as an impurity.

The ratio between said polymer and the precursor of the inorganic oxide is preferably from 1/99 w / w to 99/1 w / w, preferably, better properties are obtained when said ratio is between 25/75 and 75/25.

The total concentration of the polymer and the precursor of the inorganic oxide in the solvent is between 0.01g / ml and lg / ml.

The final solution can provide the hybrid in the desired form, for example it can be poured into a mold and left to harden at room temperature, until the massive hybrid is obtained, or it can be used to treat other materials at room temperature, for example fabrics.

It may be convenient to subsequently subject the hybrid to heat treatment to complete the reaction. The progress of the reaction can be followed by TGA and FT-IR spectroscopy, which also allow to verify its completion.

It is essential that the polymer is terminated with two OH groups.

The preparation procedure is outlined as follows:

The metal oxide is prepared from a suitable precursor, for example a metal alkoxide.

Hydrolysis:

M (0R) 4+ H20 -> M (OR) 3-OH ROH

Condensation:

M (OR) 3-OH M {OR) 3-OH (RO) 3M-M (OR) 3+ H20

and / or

M (OR) 3-OH M {OR) 3-OR -> (RO) 3M-M (OR) 3+ ROH

If a polymer terminated with two hydroxyl groups is added in the condensation phase, it is able to bind covalently during the formation process of the inorganic lattice.

An appropriate amount of polymer is weighed and dissolved in a suitable solvent, such as THF, chloroform, ethanol or 1-propanol, at room temperature (Solution 1).

In a second container the appropriate quantity of metal oxide precursor is weighed.

In the second container, first the solvent, preferably the same as the polymer or compatible with it, is added under stirring, then an acid, for example HCl (aqueous solution 37% w / v) and the dissolution is waited, verifying that the solution does not cloud (Solution 2). The mixture thus obtained is the sol of the oxide. Still stirring, solution 1 is slowly added to the oxide sol (solution 2). The mixture thus obtained (solution 1 + 2) is left under stirring for an adequate time. It is now possible to apply the 1 + 2 solution on suitable supports or to form it in a mold. The mold will be made of a material that allows the detachment of the object obtained, for example PTFE. Solution 1 + 2 is left to harden at room temperature, for example for 12-24h. The material obtained is treated in an oven, for example at 100-130 ° C for 0.5-4h, to complete the cross-linking reaction and eliminate the reaction co-products and residual solvent from the hybrid.

In a preferred embodiment of the process according to the invention, the precursor of the titanium oxide is tetraisopropoxy titanium.

In another preferred embodiment of the process according to the invention, the precursor of the zirconium oxide is zirconium tetrapropoxide

The oxide precursors are commercially available, or can be prepared by known methods.

The hybrid obtainable from the process described above is a further object of the invention.

As already mentioned, a material comprising the above described hybrid falls within the scope of the present invention.

Preferably, the material exhibits radiopacity characteristics. A suitable embodiment is a radiopaque coating, for example in the form of a film (film). The present invention includes a material for medical use, for example an endoprosthesis coated with a material comprising the hybrid described herein. An example of an endoprosthesis is a coronary stent, see EP 0824 900 and the literature relating to stents, a catheter, cardiac supports and any other type of implantable device in the body of a living subject, man or animal, which needs to be traced radiographically.

In a particularly preferred embodiment of the invention, the material comprising the hybrid is a fabric. This fabric is used for the manufacture of articles which must have radiopacity characteristics. A preferred field is the medical one, where the present invention finds application for the packaging of all those articles of clothing that are used in environments exposed to radiation. Examples are gowns, aprons, sleepers, blankets, masks, pajamas, nightgowns, gloves, and any other textile article, including bandages, sheets, curtains. Preferably, the fabric consists of natural vegetable or animal fibers such as cotton, silk, wool, or synthetic fibers, such as polyesters or polyamides, or a mixed fiber.

The fabric is treated with the hybrid of the present invention with the known and common finishing techniques, for example as described in the patent references cited in the present application.

A simple way of applying the hybrid to the fabric, for example, is impregnation with the solution from which the hybrid is prepared (solution 1 + 2 described above).

Due to the ability of the hybrids of the present invention to shield from ultraviolet radiation, another possible practical application is in the manufacture of fabrics of all kinds with the purpose of providing protection from ultraviolet radiation.

There are certain pathologies, for example Cockayne syndrome and xeroderma pigmentosum (Rapin, I, et al. Neurology, 2000, Nov 28; 55 (10): 1442-9), which require as much protection as possible from radiation. UV. In the absence of adequate protection, subjects are forced to limit their stay in the open air as much as possible, or are even forced to stay away from windows, if not properly screened or even darkened.

The present invention relates to the fabric described above for the manufacture of clothing and other accessories for protection against UV radiation.

This embodiment can also be adopted for objects of common use, for general protection from ultraviolet radiations, especially for sensitive subjects, in particular children. Examples of such applications are umbrellas, awnings, awnings, tarps, field tents.

A further object of the present invention is represented by objects with the hybrid described here, therefore transparent to visible light, but opaque to UV radiation. Examples according to the invention are transparent sheets, and their uses, for example, all the uses foreseen in construction, such as sheets for door and window frames, as windows, or openings to let light pass inside rooms or roofs of buildings, or for vehicle windows. In this way, it is possible to provide adequate protection to those subjects who need maximum protection, or otherwise want protection, without drastically reducing natural lighting.

Another interesting application is an eyeglass lens, corrective or not, for protection from ultraviolet rays.

The following examples further illustrate the invention.

Example 1: Polybutylene glutarate (PBG) / Ti02 hybrid

The quantities indicated refer to hybrid with PBG / TIPT 25/75 power supply (El-a hybrid); the quantities in brackets refer, in order, to the syntheses relating to compositions 50/50 and 75/25 (respectively El-b and El-c hybrids).

0.5g (1.0g; 1.5g) of commercial polybutylenelutarate dihydroxy terminated (PBG) (Aldrich, Catalog No. 445991, Mn1000 Da) are dissolved in 4ml of THF at room temperature (Solution 1).

Separately, 1.5g (l, 0g; 0.5g) of tetraisopropoxy titanium (TIPT) (Aldrich, 99%; Catalog No. 205273) are mixed for 2min under strong stirring with 1.0ml of THF and 120μ1 (80μ1; 40μl) of HCl (37% w / w aqueous solution, Fluka), obtaining Solution 2. Under stirring, solution 1 is slowly added to solution 2. The mixture 1 + 2 thus obtained is left under stirring for 2min.

The 1 + 2 mixture was poured into a PTFE mold and kept at room temperature for 24h. The material obtained is treated in an oven at 110 ° C for 2h, at the end of which hybrid samples indicated as El-a, El-b, El-c are obtained.

The three hybrids El-a, El-b, El-c were analyzed by thermogravimetric analysis (TGA). The results obtained are reported in Table 1. The residual weight value at 600 ° C after heating in air is attributable to the titania content in the analyzed sample and is in excellent agreement with the results calculated starting from the composition of the mixture 1 + 2.

Table 1

Thermal and spectroscopic properties of the El-a, E1-b, E1-c hybrids.

<a> Residue determined by TGA measurements in air conducted from room temperature to 600 ° C with heating 20 ° / min.

Calculated on the basis of the composition of the starting 1 + 2 mixture.

<c> Value of the wavelength at which the intensity of the transmitted radiation is reduced by 75%.

<d> Measurements carried out on hybrid samples deposited on PP, i.e. on PP-E1-a, PP-E1-b and PP-E1-c.

Figure 1 shows the FT-IR spectra of the E1-b hybrid and of the corresponding starting polymer PBG. From the comparison of the two spectra it is observed that the PBG signals are present in the hybrid, confirming the inclusion of the polymer in the ceramer, without any indication of degradation during the production of the hybrid. Furthermore, as expected, signals attributable to vibrational modes typical of Titania appear in the hybrid.

The 1 + 2 mixture was also applied on polypropylene (PP) to allow the analysis of the hybrids by UV-Vis spectrometry. PP is totally transparent to radiation in the frequency range of interest. The application of the hybrid on PP takes place by immersion (5 sec) of the samples to be covered in the 1 + 2 mixture. After extraction, the coated PP samples were kept at room temperature for 24h, followed by 1h in an oven at 110 ° C. Such samples are referred to as PP-El-a, PP-El-b and PP-El-c.

Figure 2 shows the UV-Vis spectra of the PP-El-a, PP-El-b and PP-El-c samples. For comparison, both the spectrum of the support PP and that of a solution of PBG in THF are shown in Figure 2, since in this case a homogeneous coating of polymer on PP was not obtained. The graph shows that the hybrid, even if in a thin layer (on average 5μm), strongly modifies the absorption of ultraviolet radiation, preventing the transmission of radiation at wavelengths below 320 / 340nm, acting as an excellent filter of UV radiation. Table 1 shows, by way of example, the value of the wavelength (λ25) at which the transmitted intensity is reduced by 75%.

Example 2: treatment of fabric with hybrid.

The 1 + 2 mixture of Example 1 is applied on cotton fabric. The application takes place by immersion of the samples to be covered in the mixture 1 + 2 for 15 sec. The coated cotton samples were left at room temperature for 24h, followed by 1h treatment in an oven at 110 ° C. At the end of the treatment, fabric samples with hybrid coating indicated as Cot-E2-a, Cot-E2-b, Cot-E2-c are obtained.

The Cot-E2-a, Cot-E2-b, Cot-E2-c samples were analyzed by TGA. The results obtained are reported in Table 2.

Table 2

Results from thermogravimetry of tissue samples treated with Cot-E2-a, Cot-E2-b, Cot-E2-c hybrid.

<a> Residue determined by TGA measurements in air conducted from room temperature to 60.0 ° C with heating 20 ° / min.

Calculated on the basis of the composition of the starting mix 1 + 2, and the amount of hybrid deposited on the cotton.

As already discussed in Example 1 for the hybrids El-a, El-b, El-c, also in Cot-E2-a, Cot-E2-b, Cot-E2-c the residue value at 600 ° C in air is attributable to the titania content of the analyzed sample. In fact, there is good agreement between the experimental data and the calculated one (taking into account the quantity of hybrid deposited on the cotton and the composition of the starting 1 + 2 mixture). This result demonstrates that in the phase of deposition on fabric the composition of the hybrid remains unchanged and can be controlled by changing the composition of the 1 + 2 mixture.

Figure 3 compares the scanning electron microscope (SEM) images of the fabric before (a and c, images at different magnification, x100 and x1000) and after treatment with hybrid (b and d, sample Cot-E2-b). No evident differences are observed in the appearance of the two fabrics, not even at x100 magnification (images c and d), where the single fibers that make up the hybrid treated yarn appear distinct and separate from each other, as in the untreated sample. The presence of fibers individually covered by the hybrid is the result of a coating that does not macroscopically and indistinctly include the entire yarn, thus not obstructing the porosity of the fabric.

Example 3: PBG / TiO2 hybrid with water

1.0g of commercial PBG is dissolved in 5ml of THF at room temperature (Solution 3).

Separately, 1.0g of tetraisopropoxy titanium (TIPT) with 1.0ml of THF and 80μl of HC137% w / w (Solution 4) are mixed for 2 min under strong stirring. Under stirring, solution 3 is slowly added to solution 4. The mixture 3 + 4 thus obtained is left under stirring for 5 '. Separately, a solution of Η20 (variable quantity in the range 60-180 μl) in 1.0ml of THF (solution 5) is prepared. Solution 5 is slowly added to solution 3 + 4 under strong stirring, obtaining solution 3 + 4 + 5.

The 3 + 4 + 5 mixture is poured into a PTFE mold and left to 'age' at room temperature for 24h. The material obtained is treated in an oven at 110 ° C for 2h, thus obtaining the hybrid.

From the comparison of the FT-IR spectra of the obtained hybrids with the spectrum of the starting PBG polymer, it emerges that the PBG signals are maintained in the hybrid, confirming the inclusion of the polymer in the ceramer without evident degradation. Furthermore, new signals appear attributable to vibrational modes typical of Titania.

Example 4: Polytrimethylene carbonate (PTMC) / Titania hybrid

Following the procedure of Example 1, except for the preparation of solution 1, PTMC / Titania hybrids were prepared.

Preparation of solution 1: 0.5g (1.0g; 1.5g) dihydroxy-terminated polytrimethylene carbonate (PTMC; average molecular weight 2500Da evaluated from H-NMR spectra) synthesized according to procedures known in literature [M. Sepulcher, M. 0. Sepulcher, M. A. Dourges, and M. Neblai, Macromolecular Chemistry and Physics, 201, 1405 (2000)] is dissolved in 6ml of THF at room temperature.

From the comparison of the FT-IR spectra of the hybrids obtained with the spectrum of the starting polymer PTMC it is observed that the PTMC signals are present in the hybrid, confirming the inclusion of the polymer in the ceramer, without indications of degradation during the production of the hybrid. Furthermore, as expected, signals attributable to vibrational modes typical of the Titania appear in the hybrid.

Example 5: PTMC / Titania hybrid

Following the procedure of Example 1, except for the preparation of solution 1, PTMC / Titania hybrids were prepared.

Preparation of solution 1: 0.5g (1.0g; 1.5g) dihydroxy terminated polytrimethylene carbonate (PTMC; average molecular weight 3900Da evaluated from <1> H-NMR spectra) synthesized according to procedures known in literature [M. Sepulcher, M. 0. Sepulcher, M. A. Dourges, and M. Neblai, Macromolecular Chemistry and Physics, 201, 1405 (2000}] is dissolved in 6ml of THF at room temperature.

From the comparison of the FT-IR spectra of the hybrids obtained with the spectrum of the starting polymer PTMC it is possible to observe that the PTMC signals are present in the hybrid, confirming the inclusion of the polymer in the ceramer, without any indications of degradation during the production of the hybrid. Furthermore, as expected, signals attributable to vibrational modes typical of Titania appear in the hybrid.

Example 6: PDEGA / Titania hybrid

Following the procedure of Example 1 except for the preparation of solution 1, PDEGA / Titania hybrids were prepared.

Preparation of solution 1: 0.5g (1.0g; 1.5g) of commercial dihydroxy terminated polydethylene glycoleadipate (PDEGA) (Aldrich, Catalog No. 458392, Mn2500Da} is dissolved in 6ml of THF at room temperature.

From the comparison of the FT-IR spectra of the hybrids obtained with the spectrum of the starting polymer PDEGA it is observed that the PDEGA signals are present in the hybrid, confirming the inclusion of the polymer in the ceramer, without any indications of degradation during the production of the hybrid. Furthermore, as expected, signals attributable to vibrational modes typical of Titania appear in the hybrid.

Example 7: Polybutylene glutarate (PBG) / Zr02 hybrid

0.5g (1.0g; 1.5g) of commercial polybutylenelutarate dihydroxy terminated (PBG) (Aldrich, Catalog No. 445991, Mn1000 Da) are dissolved in 6ml of THF at room temperature (Solution 1).

Weigh separately 2.15g (l, 43g; 0.72g) of commercial solution of zirconium tetrapropoxide (TPOZ) in 1-propanol (Aldrich, 70% w / w solution, Catalog No. 333972) (Solution 2). Under stirring, solution 1 is slowly added to solution 2. The mixture 1 + 2 thus obtained is left under stirring for 2min.

The 1 + 2 mixture was poured into a PTFE mold and kept at room temperature for 24h. The material obtained was treated in an oven at 110 ° C for 2h thus obtaining the hybrid.

From the comparison of the FT-IR spectra of the hybrids obtained with the spectrum of the starting PBG polymer, it is observed that the PBG signals are present in the hybrid, confirming the inclusion of the polymer in the ceramer, without any indications of degradation during the production of the hybrid. Furthermore, as expected, signals attributable to vibrational modes typical of zirconia appear in the hybrid.

Example 8: Polybutylene glutarate (PBG) / Zr02 hybrid

0.5g (1.0g; 1.5g) of commercial polybutylenelutarate dihydroxy terminated (PBG) (Aldrich, Catalog No. 445991, Mn1000 Da) are dissolved in 6ml of THF at room temperature, then 92μ1 (61μ1; 30μ1) are added ) of HC1 (aqueous solution 37% wt, Fluka) (Solution 1).

Weigh separately 2.15g (l, 43g; 0.72g) of commercial solution of zirconium tetrapropoxide (TPOZ) in 1-propanol (Aldrich, 70% w / w solution, Catalog No. 333972) (Solution 2). Under stirring, solution 1 is slowly added to solution 2. The mixture 1 + 2 thus obtained is left under stirring for 2min.

The 1 + 2 mixture was poured into a PTFE mold and kept at room temperature for 24h. The material obtained is treated in an oven at 110 ° C for 2h, thus obtaining the hybrid.

From the comparison of the FT-IR spectra of the hybrids obtained with the spectrum of the starting PBG polymer, it is observed that the PBG signals are present in the hybrid, confirming the inclusion of the polymer in the ceramer, without any indications of degradation during the production of the hybrid. Furthermore, as expected, signals attributable to vibrational modes typical of zirconia appear in the hybrid.

Example 9: treatment of fabric with hybrid.

The 1 + 2 mixture of Example 8 is applied on cotton fabric. The application takes place by immersion of the samples to be covered in the mixture 1 + 2 for 15 sec. The coated cotton samples were left at room temperature for 24h, followed by 1h treatment in an oven at 110 ° C. At the end of the treatment, fabric samples with hybrid coating indicated as Cot-E9-a, Cot-E9-b, Cot-E9-c are obtained.

The Cot-E9-a, Cot-E9-b, Cot-E9-c samples were analyzed by TGA. The results obtained are reported in Table 3.

Table 3: Results from thermogravimetry of tissue samples treated with Cot-E9-a, Cot-E9-b, Cot-E9-c hybrid.

<a> Residue determined by TGA measurements in air conducted from room temperature to 600 ° C with heating 20 ° / min.

Calculated on the basis of the composition of the starting mix 1 + 2, and the amount of hybrid deposited on the cotton.

As already discussed in Example 2 for the Cot-E2-a, Cot-E2-b, Cot-E2-c hybrids also in Cot-E9-a, Cot-E9-b, Cot-E9-c the residue value at 600 ° C in air it is due to the zirconia content of the analyzed sample. In fact, there is good agreement between the experimental data and the calculated one (taking into account the quantity of hybrid deposited on the cotton and the composition of the starting 1 + 2 mixture). This result demonstrates that in the phase of deposition on fabric the composition of the hybrid remains unchanged and can be controlled by changing the composition of the 1 + 2 mixture.

The coated fabrics were observed under a scanning electron microscope and compared to SEM images of the uncoated hybrid cotton fabric. There are no obvious differences in the appearance of the two fabrics. The single fibers that make up the hybrid treated yarn appear distinct and separate from each other, as in the untreated sample. The presence of fibers individually covered by the hybrid is the result of a coating that does not macroscopically and indistinctly include the entire yarn, thus not obstructing the porosity of the fabric.

Similarly, silk, wool and polyester fabrics were treated.

Claims (44)

CLAIMS 1. Organic-inorganic hybrid consisting of: to. inorganic oxide b. chosen polymer an aliphatic polyester, aliphatic polyetherester, aliphatic polycarbonate, aliphatic polyetherecarbonate and a copolymer thereof in which the oxide and the polymer are covalently bonded. 2. Hybrid according to claim 1, wherein said inorganic oxide is selected from the transition metal oxides of Group IV A of the Periodic Table of the elements. 3. Hybrid according to claim 2, wherein said oxide is selected from zirconium oxide (zirconia), titanium oxide (titania), yttrium oxide, cerium oxide, tantalum oxide, hafnium oxide, molybdenum oxide and oxide of niobium. 4. Hybrid according to one of claims 1 to 3, wherein said polymer is represented by the following formulas: in which: a is selected between 0,1,2,3,4 and 5; b is chosen between 0 and 1; c is selected between 0,1,2,3,4 and 5; d is selected between 0,1,2,3,4 and 5; and is selected from 0.1; the various a, b, c, d and e being equal or different in the two blocks n and m; Ri / R2 / R3 / R4, equal or different from each other, are H, (CH2) kCH3, in which k is chosen between 0,1,2,3,4 and 5, or Ri and R2 are linked together to form a cycloalkylene; Rs is selected from a group - (CR6R7) i- / where 1 is an integer between 1 and 20, where R6 and R7, the same or different, are hydrogen or a C1-C8 alkyl group, linear or branched and a group - [(CR8R9) P-X] r- where RBe R9, equal or different from each other, are hydrogen or a C1-C8 alkyl group, linear or branched and a group and X is chosen from 0, S and NH, where r is an integer between 1 and 100 and p is an integer between 1 and 10; or: in which: a is selected between 0,1,2,3,4 and 5; b is chosen between 0 and 1; c is selected between 0,1,2,3,4 and 5; d is selected between 0,1,2,3,4 and 5; e is chosen between 0 and 1; f is selected between 0,1,2,3,4 and 5; a and c being equal or different in the two portions of the molecule; Ri / R-2 / ^ 3 / R4 / R5 / R6 / R7 / Ra equal or different from each other, are H, (CH2) kCH3, where k is chosen between 0,1,2,3,4 and 5. 5. Hybrid according to claim 4, wherein said polymer or copolymer has a molecular weight Mn comprised between 200 and 50000 Da. 6. Hybrid as claimed in claim 1, wherein said aliphatic polyester is selected from the group consisting of polylactic acid, polyglycolic acid, polyhydroxybutyric acid, polycaprolactone, polydioxanone, polypivalolactone, polyethylene adipate, polybutylenadipate, polybutyleneglycol acetate, polyethylene glycolate, polyethylene glycolate, polyethylene glycolate , while said polycarbonate or aliphatic polyetherecarbonate is polyethylene carbonate, polythrimethylene carbonate, polyhexamethylene carbonate, poly (2,2-dimethyl) propylene carbonate, polycyclohexanecarbonate, poly (ethylene ether-carbonate), poly (propylene ether-carbonate). 7. Hybrid according to claim 6, wherein said aliphatic polycarbonate is polytrimethylene carbonate. 8. Hybrid according to claim 6, wherein said aliphatic polyester is selected from polybutylene glutarate and polydethylene glycol adipate. Hybrid according to one of the preceding claims, in which the inorganic phase is in the nanometric domain. 10. Process for the preparation of the hybrid of claims 1-9, comprising the preparation of an inorganic oxide in the presence of a selected polymer an aliphatic polyester, aliphatic polyetherester, aliphatic polycarbonate, aliphatic polyetherecarbonate and a copolymer thereof, said polymer or its di-hydroxy terminated copolymer. 11. Process according to claim 10, wherein said inorganic oxide is prepared according to the sol-gel method. 12. A process according to claim 11, wherein a solution of said polymer is added to a precursor solution of said inorganic oxide to give a precursor solution of said hybrid. 13. Process according to claim 12, wherein the solvent of said solution of said polymer is the same solvent of said precursor solution of said inorganic oxide. 14. Process according to claim 12 or 12, wherein said solvent is selected from tetrahydrofuran, chloroform, ethanol or 1-propanol. 15. Process according to claim 14, wherein said polymer is dissolved in tetrahydrofuran. 16. Process according to claim 14, wherein said precursor of said inorganic oxide is dissolved in tetrahydrofuran. 17. Process according to one of claims 10-16, wherein said solution of said inorganic oxide precursor contains an acid. 18. Process according to claim 17, wherein said acid is an inorganic acid. 19. Process according to claim 18, wherein said acid is selected from hydrochloric acid and sulfuric acid. Process according to one of claims 10-19, wherein said solution of said precursor of said hybrid is added to an aqueous solution of the solvent. 21. Process according to one of claims 10-20, wherein the ratio between said polymer and said precursor of said inorganic oxide is from 1/99 w / w to 99/1 w / w. 22. Process according to one of claims 10-21, wherein the total concentration of the polymer and of the precursor of said inorganic oxide is comprised between 0.01g / ml and 1g / ml. 23. Process according to one of claims 10-22, wherein said precursor solution of said hybrid is allowed to harden at room temperature. 24. Process according to claim 23, wherein said hybrid is further heat treated. 25. Process according to one of claims 10-24, wherein said inorganic oxide precursor is selected from tetraisopropoxy titanium and zirconium tetrapropoxide. 26. Process according to one of claims 10-25, wherein said polymer is selected from the group consisting of dihydroxy terminated polybutyleneglutarate and polydethyleneglycol adipate and said precursor of said inorganic oxide is tetraisopropoxy titanium. 27. Process according to one of claims 10-25, wherein said polymer is dihydroxy terminated polytrimethylene carbonate and said precursor of said inorganic oxide is tetraisopropoxy titanium. 28. Hybrid obtainable by the process of claims 10-27. 29. Material comprising the hybrid of claims 1-8 or of claim 28. 30. A material according to claim 29 which is a radiopaque coating. 31. A material according to claim 30, wherein said coating is in the form of a film. 32. Material comprising the hybrid of claim 9 or claim 28. 33. Transparent plate comprising the material of claim 32. 34. Lens comprising the material of claim 32. 35. Endoprosthesis coated with the material of claim 29. 36. An endoprosthesis according to claim 35 which is a coronary stent. 37. A material according to claim 29 which is a fabric. 38. A material according to claim 35, wherein said fabric is formed from natural vegetable or animal or synthetic fibers. 39. Material according to claim 36, wherein said fabric is formed by a fiber selected from cotton, silk, wool, polyesters or polyamides or a mixed fiber. 40. Garment comprising the material of one of claims 37-39. 41. A textile article comprising the material according to claim 29. 42. Composite comprising the hybrid of claims 1-9 or 28. 43. A composite according to claim 42, comprising silver salts. 44. Use of the composite of claim 34 as an antibacterial agent. 36. An endoprosthesis according to claim 35 which is a coronary stent. 37. Material according to claim 29, which is a fabric, 38. A material according to claim 35, wherein said fabric is formed from natural vegetable or animal or synthetic fibers. 39. Material according to claim 36, wherein said fabric is formed by a fiber selected from cotton, silk, wool, polyesters or polyamide or a mixed fiber. 40. Garment comprising the material of one of claims 37-39. 41. A textile article comprising the material according to claim 29. 42. Composite comprising the hybrid of claims 1-9 or 28. 43. A composite according to claim 42, comprising silver salts. 44. Use of the composite of claim 43 as an antibacterial to people.