# Surface Modification of Glass Textile for the Reinforcement of a Cement-Based Composite: A Review
## 5 Conclusions  
Although the number of studies conducted on the surface modification of glass fibers for the reinforcement of cementitious matrices is still limited, compared to the wide scientific production available for organic matrices, different promising techniques have been described in the literature and can be used to improve the mechanical performance and durability of this class of composites. Because of the great variety of cementitious matrices that can be employed, as well as their different applications, that ranges from the production of high-performance building elements to the reinforcement of existing structures, there is no single solution. On the contrary, the possibility of using different techniques allows us to tailor the reinforcement and the fiber-matrix interface properties according to the specific application.  
Based on the results presented, some conclusions can be drawn:  
* In general the improvement of the load-bearing capacities of the composites by impregnation of the reinforcement with a polymeric coating is mainly due to the superior wettability of the polymer compared to the cementitious matrix, and its ability to fully penetrate in multi-filament yarns promoting a superior stress-transfer between the fibers.
* On the basis of the studies available it is not possible to state which polymeric coating provides the highest performance. In general, it has been observed that stiffer coatings like epoxy resins improve the composite tensile strength. However, epoxy impregnated reinforcements are also reported to have low flexibility, which can be a disadvantage when fabrics are meant to be used for the reinforcement of existing structures with complex geometry. Moreover, although a stiffer reinforcement can improve the tensile strength of the composite, flexible textiles performed better under flexural load. These parameters should be considered according to each specific use.
* For what it concerns the fiber-matrix interface, the interaction between polymeric coatings and inorganic matrices strongly depend on the chemical composition of the coating and can be improved by using the fresh to fresh methods or by incorporating inorganic particles, such as nanoclay, in the polymeric matrix. Since the first method is less feasible for strengthening interventions, it seems more suitable for the production of TRC elements rather than for FRCM applications. On the contrary, the second method can be used also for the production of pre-impregnated fabrics for the rehabilitation of existing structures.
* A stronger fiber-matrix interaction can be obtained by using inorganic coatings, which can chemically react with the cementitious matrix, providing a better adhesion at the fiber-to-matrix interface. However, a strong fiber-matrix interaction also results in a stiffer fiber-matrix interface, which could make the composite more brittle and lead to a reduction of the mechanical performance over time.  
Conceptualization, F.B. and J.D.; writing--original draft preparation, F.B.; writing--review and editing, F.B. and J.D.; visualization, F.B.; supervision, J.D.; All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
The authors declare no conflict of interest.