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1st Central European Conference on Regenerative Medicine, Bydgoszcz, 2015

INTRODUCTIONINTRODUCTIONDuring the past two decades significant advances have been made in the development of materials for bio-medical applications. The paper presents the results of studies on ceramics-polymer composites [1]. The purpose of the research consists in manufacture and test functionally graded biocomposite made by filling porous alumina ceramics by biodegradable polymers. The idea of the composite is that the polymer degrades and in the empty space tissue will grow [2], which allows a permanent connection of implants with the bone tissue.

MATERIALS AND METHODSMATERIALS AND METHODSPorous alumina material (AL) was formed by polymeric sponge method [3] using structural sponges of dif-ferent pore per inch density. During forming, a 3D structure of interconnected posts was shaped. Struc-tures of different size of spaces between posts and differing total porosity can be obtained by the selection of the sponge density (Fig. 1). Biodegradable polyurethanes (PU) based on poly(�-caprolactone)diol (PCL) and 4,4`-diisocyanato-methylenedicyclohexane (HMDI) were obtained. As chain extenders two different agents were used: ethylene glycol and water (Fig. 2). The biocomposites were obtained by infiltration of po-rous ceramics with prepolymers, solidified in the final stage due to crystallization [4]. The prepolymer was crystalized at various temperatures, and subsequently chain-extended with water.

Scanning electron microscopy (SEM) was used to investigate the composites microstructure. Compressive strength of porous alumina ceramics, of poly(�-caprolactono)diol polyurethanes obtained from crystalline prepolymers extended by water and of the composites fabricated by infiltration method was tested.

RESULTSRESULTSThe main physical properties of porous alumina are, as follows: pore size - 130÷900 μm, total porosity - 84÷90 %, compressive strength (σ) - up to 5,5 MPa (Fig. 6).

Advantage of the biodegradable polymers made in a reaction of prepolymer with water as a chain extender is its long pot-life, low viscosity before curing and high compressive strength (Fig. 3) [5].

The alumina-polymer composite is characterized by much higher compressive strength than alumina foam itself (up to 6 times) and doesn’t loose its cohesion even after large deformation, even up to 50% (Fig. 4). SEM images of composite microstructure are shown on Fig. 5. For both types of polyurethanes (chain-extended with water as well as with glycol) the pores are fully filled with polymer without any voids and cracks.

SUMMARYSUMMARYThe presented investigations demonstrated that we could fabricate composites on the basis of porous alu-mina ceramic filled with polyurethane obtained from crystalline prepolymers chain extended with water. The results showed that pores of ceramics were fully filled with polyurethanes. The alumina ceramics-bio-degradable polymer composites exhibit much higher resistance for compressive stresses than porous alu-mina itself and higher rigidity than polyurethanes.

These kind of composites give new perspectives for medical applications, because it assembles with bio-compatible components and have better mechanical properties than porous alumina foams. After particu-lar biological tests the material could be used for design and future production of biomimetic type of small joints prosthesis.

ALUMINA-POLYURETHANE COMPOSITE ALUMINA-POLYURETHANE COMPOSITE FOR MEDICAL APPLICATIONFOR MEDICAL APPLICATION

This work was fi nanced by Polish Ministry of Science and Higher Education (grant nr This work was fi nanced by Polish Ministry of Science and Higher Education (grant nr 3 T08D 03129)T08D 03129)

Zbigniew JaegermannZbigniew Jaegermann1, Agata Domańska, Agata Domańska2, Anna Boczkowska, Anna Boczkowska2, Artur Oziębło, Artur Oziębło1, Monika Biernat, Monika Biernat1

1. Institute of Ceramics and Building Materials, Department of Ceramic Technology, Warsaw, Poland1. Institute of Ceramics and Building Materials, Department of Ceramic Technology, Warsaw, Poland2. Warsaw University of Technology, Faculty of Materials Science and Engineering, Warsaw, Poland2. Warsaw University of Technology, Faculty of Materials Science and Engineering, Warsaw, Poland

1st Central EEuropean Conference on

Fig. 2. Microstructure of polymers (SEM images)

Fig. 1. Porous structures of alumina material (stereomicroscopic images)

PCL/HMDI/EG PCL/HMDI/W

45 ppi 90 ppi 1 mm 1 mm

Fig. 6. Load/extension curves of porous alumina

45 ppi σ = 2,1÷3,0 MPa

90 ppiσ = 2,2÷5,5 MPa

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Fig. 4. Compressive curves of porous alumina, polymer and polymer-alumina composite

Fig. 3. Compressive curves of polymers

PCL/HMDI/EG

PCL/HMDI/W

1. Boczkowska A., Jaegermann Z., Domańska A., Kurzydłowski K.J., Babski K.: Poliuretan bioresorbowalny, sposób wytwarzania poliuretanu bioresorbowalnego, kompozyt ceramika-poliuretan bioresorbowalny i sposób wytwarzania kompozytu ceramika-poliuretan bioresorbowalny. Polish Patent nr PL-212636, 2012

2. Jaegermann Z., Boczkowska A., Paszewska A., Michałowski S.: „Ceramiczno-polimerowy materiał gradientowy do zastosowania w endoprotezoplastyce stawów - doniesienie wstępne”. Prace Komisji Nauk Ceramicznych PAN, CERAMIKA, 2008, 101, 41-48

3. W. P. Minnear: Processing of porous ceramics. Am. Cer. Soc. Bull., 71, 11, 1992

4. Szafran M., Boczkowska A., Konopka K., Kurzydłowski K., Rokicki G., Batorski K.: Kompozyt ceramiczno-polimerowy i sposób wytwarzania kompozytu ceramiczno-polimerowego. Polish Patent nr PL-198281, 2008

5. Jaegermann Z., Boczkowska A., Domańska A., Michałowski S.: „Ceramic-Polymer Functional Gradient Biocomposite for Joints Endoprosthesis Applications”. 8th World Biomaterials Congress, Amsterdam, 2008

Fig. 5. Microstructure of polymer-alumina composites (SEM images)

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AL AL

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PU

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PU PU

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PCL/HMDI/W-AL

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