vulcanization in the presence of moisture such as that provided by atmospheric humidity can be employed with good effect the material incorporated into the formulation used to manufacture the rubber material to which the adhesive makes contact has a solubility parameter in the range of 8 5 to 10 5 cal 1 2 cm 3 2 mol u2212 1 further this material contains chemical groups able to attract and weakly bond with water molecules either through hydrogen bonding or other weak chemical interaction such bonding or interaction capacity can be found for example in molecules having end groups such as u2014 oh u2014 ooh u2014 nh u2014 nh 2 and combinations thereof specific examples of operative materials are esters such as sorbitan monostearate and formaldehyde resins such as octylphenol formaldehyde resin the following examples demonstrate the moisture absorbing and thereby the adhesion facilitating function of the rubber additive described herein which has been incorporated into a rubber innerliner formulation the formulations for evaluating the adhesion facilitating rubber additive are set out below in tables 1 and 2 the formulations are divided into first non productive mixes and second productive mixes all component concentrations are referenced on a weight basis to parts per hundred rubber phr the rubber additive evaluated in the table 1 formulation was octylphenol formaldehyde resin having a solubility parameter of 10 1 cal 1 2 cm 3 2 mol u2212 1 from lonza inc allendale n y the rubber additive evaluated in the table 2 formulation was sorbitan monostearate having a solubility parameter of 9 41 cal 1 2 cm 3 2 mol u2212 1 from schenectady international schenectady n y the four rubber samples prepared.