FCS3

Table 8 Predicted Crumb Rubber Attribute Effects Matrix for Case Study 1

Dir of Change

Flexural Strength

Impact Strength

Coeff of Friction

Comp Set

Abrasion Resist

Tensile Strength Hardness Flammability

Attribute

Particle Size*

NA

NA

NA

NA











Particle Size Distribution

Broad

−

−

−

−









Heat history

−

−

−

−

−









Loading



















   

Surf Area

− 

−  

− 

− 

* Poor interfacial adhesion is assumed since this is typical in most crumb rubber filled applications Product development work for this TDP is ongoing by the manufacturer and their suppliers. Additional testing is needed to determine if the current design with the current crumb rubber raw material is fit for its intended use. Further work is needed to determine the crumb rubber material characteristics that are needed to produce a suitable and reproducible product. Case Study 2 – Coating Manufacturer (Company B) Company B is developing a coating using crumb rubber as an aggregate. The process was initiated by interviewing company B about the use and performance expectations for the TDP. A competitive assessment was conducted which identified 14 functionally similar products. Seven products were considered in-kind competitors that also incorporated crumb rubber. Tests were conducted and performance characteristics were compiled and compared against stated performance expectations. Key product characteristics that are directly affected by crumb rubber and data collected for the case study are presented in Table 9.

Contractor’s Report

23