Synthesis and Properties of Flexible Polyurethane Using Ferric Catalyst for Hypopharyngeal Tissue Engineering

Abstract

Biodegradable polyurethane is an ideal candidate material to fabricate tissue engineered hypopharynx from its good mechanical properties and biodegradability. We thus synthesized a hydrophilic polyurethane via reactions among polyethylene glycol (PEG), e-caprolactone (e-CL) and hexamethylene diisocyanate (HDI), and thrihydroxymethyl propane (TMP). The product possessed a fast degradability due to its good wettability and good mechanical parameters with the elongations at break (137 ± 10%) and tensile strength (4.73 ± 0.46 MPa), which will make it a good matrix material for soft tissue like hypopharynx. Its biological properties were evaluated via in vitro and in vivo tests. The results showed that this hydrophilic polyurethane material can support hypopharyngeal fibroblast growth and owned good degradability and low inflammatory reaction in subcutaneous implantation. It will be proposed as the scaffold for hypopharyngeal tissue engineering research in our future study.

T-Shaped Microfluidic Junction Processing of Porous Alginate-Based Films and Their Characteristics

“…The characteristic absorption peak at 958 cm −1 represents the groups of C–H. These results show similarity with the spectra already given in the literature [35,36,37]. Alginate–PEG-40S films or alginate–PEG-40S–phospholipid films show almost the same absorption peaks as pure alginate and PEG-40S, accompanied by some slight shifts.…”

Efeito da estrutura molecular de copolímeros multiblocos de poli(&#949;-caprolactona->i<b>/i<-etileno glicol) na compatibilidade de blendas biodegradáveis de poli(ácido láctico)/poli(&#949;-caprolactona)

“…O isocianato pode ciclotrimerizar, formando grupos isocianuratos na presença de catalisadores de trimerização e são utilizados na fabricação de espumas rígidas para construção civil devido a formação de uma rede tridimensional reticulada que confere resistência térmica e à propagação de chamas (SONNENSCHEIN, 2015). PEEUs já se mostraram serem biodegradáveis e aptos para serem utilizados em scaffolds biocompatíveis, suturas bioabsorvíveis, sistemas de liberação controlada de fármacos e outras aplicações para Engenharia de Tecidos (tissue engineering -TE) (BARTOLOZZI et al, 2011;SHEN et al, 2015;KUPKA et al, 2016) De acordo com as reações apresentadas acima, a degradação de PU se inicia com a quebra das ligações uretânicas presentes nos segmentos mais rígidos, gerando quantidades de isocianatos de acordo com o esquema (1). Em altas temperaturas, superiores a 350°C, as reações (2) e (3) dominam o processo de degradação.…”