04-12 Introduction to “TVS mud index” as an evaluation marker of silt-clayey matrices for bioadhesive thermal and cosmetic applications / 日本温泉気候物理医学会雑誌

ABSTRACT

Introduction: Brenta’s silt-clay consist of silt with clay containing Italian Dolomites minerals extracted from the catchment area of Brenta river. Sediments were investigated by SEM, XRD, XRF and particle size granulometer. The presence of SiO2 (34.16%), CaO (17.12%), and Al2O3 (11.15%) as principal elements is comparable with the typical composition of Euganean Thermal Muds (ETM) of Euganean Thermal Area (ETA) which average level of SiO2, CaO, and Al2O3 are respectively 38.75%, 17.74%, and 7.70%1). Tensiometric investigation of Brenta’s silt-clay were performed hypothesizing its employ in mudtherapy. Objectives: Surface energy of natural ETM and its maturation process were monitored by TVS mud index, a tensiometric marker for the determination of the quality of a thermal mud2). The aim of this work was to determine the quality of Brenta’s silt-clay by tensiometric approach introducing it in the field of thermalism. Materials and Methods: Brenta’s silt-clayey (ie Brenta Ker) samples were collected from EGAP’s gravel pit, undergone at maturation process for 6 weeks employing thermal water, investigated using DSA10-Kruss tensiometer with diiodomethane, PFPE, glycerine as liquid tests.   Tensiometric characterizations were performed by measurement of contact angles (deg) of different liquid tests and their conversion in surface energy (mN/m) by Owens mathematical model 3). TVS mud index levels were determined trough the measurements of contact angles of PFPE 4) by Perfluoropolyether Contact Angle Measurement Method (PCAM) for maturation process (mN/m eq./weeks) and speed (m*Nm-1/h) evaluations. Results: The correlation degree between ETM XRF elements data (ppm) and those of Brenta’s silt-clay (ppm) was satisfactory (R2=0.82) confirming the common origin of two kind of matrices. Considering 6 weeks of maturation, surface energy profile of Brenta’s silt-clay, expressed as dispersed component (DC) and polar component (PC), showed respectively 17.84 mN/m and 32.04 mN/m with coefficients of variations (CV%) around 22.43% and 14.29%. TVS mud index levels monitored during maturation process showed a clear decrease in the time (t0=84.02.5 mN/m eq, t1=71.01.9 mN/m eq., t2=79.80.7 mN/m eq., t3=72.63.1 mN/m eq., t4=61.22.6 mN/m eq., t5=65.12.1 mN/m eq., t6=58.81.6 mN/m eq.) underlined by the decrease of maturation speed monitored for 60 days and expressed as DC per hour (t48=0.08 m*Nm-1/h, t120=0.03 m*Nm-1/h, t144=0.04 m*Nm-1/h, t384= 0.02 m*Nm-1/h, t1416=0.005 m*Nm-1/h). Conclusions: Tensiometric investigations by TVS modelling and maturation speed evaluations confirmed the suitability of Brenta’s silt-clay to be employed in thermal field opening new perspectives in mudtherapy.