Towards greener stone shot and stone wool materials: binder systems based on gelatine modified with tannin or transglutaminase

Abstract

In the pursuit of greener stone wool and related materials, the development, study and discussion of strong binder systems for such materials based on gelatine modified with tannin or transglutaminase are presented. The first systematic studies and direct comparisons of gelatines with four different gel strengths modified with 3-50% chestnut tree tannin or transglutaminase are presented and discussed.The development of these non-toxic, biopolymer-based binder systems was achieved using composite bars comprising stone shots with submillimeter diameters as a versatile model for stone wool. Contrary to conventional binder systems, the gelatine-based binder systems were able to cure at ambient temperature, and increased unaged and aged mechanical strengths combined with decreased binder solubility were generally observed as a function of increased gel strength and viscosity of the gelatine component.Several of the compositions resulted in mechanical strengths before and after ageing treatments that were within the range of conventional binder systems. Intriguingly, the gelatine-based binder compositions generally appeared less sensitive towards ageing treatment than conventional binders and in several cases even displayed mechanical strengths after ageing treatments that were at a similar level or better than the corresponding unaged strengths. The developed binder systems thus displayed unprecedented "self-healing" properties. The first DMA studies of cross-sections of the composite bars showed that these binder systems could withstand temperatures well above those required and/or commonly encountered in for example the production and general use of stone wool products. The first SEM studies of the composite bars revealed that the binders created a honeycomb-like structure around the stone shots with several thinner bridging points between adjacent stone shots. The development of this highly promising new generation of bio-inspired binder technologies is expected to enable the manufacture of greener stone wool and related materials through the use of non-toxic and natural components that enable an environmentally improved route to these materials via the reduction of adverse environmental effects such as high energy consumption and emissions during the curing process.

Waste Mineral Wool and Its Opportunities—A Review

“…Waste rock wool is contaminated in two phases. The first phase is during the manufacturing process, where hazardous materials such as phenol-formaldehyde binders are coated onto the fiber surface [ 54 ]. The second phase is during the application process, where the waste rock wool becomes contaminated with other pollutants such as mycological substances, impurity dust, or chemical substances.…”

Penggunaan DNA Mitokondria Sebagai Penanda Sumber Gelatin Sediaan Gummy dengan Teknik Polymerase Chain Reaction dan Sekuensing DNA

“…Gelatin adalah protein yang diperoleh dari jaringan kolagen hewan yang terdapat pada kulit, tulang dan jaringan ikat. Pada prinsipnya, proses pembuatan gelatin dibagi menjadi dua, yaitu hidrolisis dengan larutan asam atau dengan larutan basa, yang umumnya bersumber dari sapi dan babi [2]. Namun, penggunaan sumber gelatin dari jenis tertentu lebih dibatasi, sehingga identifikasi sumber penting dilakukan [3].…”

Gelatin–Tannin-Based Greener Binder Technology for Stone Shot and Stone Wool Materials: A Detailed Study

“…5 − 9 Accordingly, the first systematic studies and direct comparisons of various properties of binder systems based on type A gelatins modified with tannin from chestnut trees in the presence of NaOH at pH 9 or with transglutaminase at pH 5 were recently published. 10 As an essential element in advancing and understanding the greener binder technology based on gelatins modified with tannins, this paper presents the first systematic studies of the effects of varying the nature of the gelatin component, the tannin component, the metal cation of the hydroxide base, and the final pH. Apart from unaged and aged mechanical strengths and binder solubilities obtained from the use of a convenient composite bar model method, the first systematic water uptake studies of all of the binder compositions and comparisons with contact angles of selected series are likewise reported.…”

“…In addition to warm water solubility and gel formation, gelatin is able to form strong films and displays adhesive properties. 10 − 14 However, it is also often desirable (though not always necessary) that the final dried and cured binder system is able to withstand humid or wet conditions. To that end, many phenolics 15 such as the structurally immensely diverse tannins 16 − 19 are well known for their capacity to interact strongly with proteins such as gelatin.…”

“…To that end, many phenolics 15 such as the structurally immensely diverse tannins 16 − 19 are well known for their capacity to interact strongly with proteins such as gelatin. 10 , 12 , 16 , 17 , 20 − 29 One important class of tannins is the hydrolyzable tannins, which comprise gallotannins and ellagitannins ( Figure 1 , bottom left and mid, respectively). 16 − 18 Another important class of tannins consists of the condensed tannins or proanthocyanidins ( Figure 1 , bottom right).…”