This article reports the facile synthesis of novel terminally and centrally functionalized polyisobutylenes (PIBs) and the detailed characterization of the products by various mass spectrometry techniques. Specifically, HOPIBOCH 2 OC(OH)CH 3 O CH 2 ONHCH 3 and [HOPIBOCH 2 OCH(OH)CH 3 OCH 2 ] 2 ONCH 3 were synthesized by the quantitative epoxidation of HOPIBOCH 2 OC(CH 3 )ACH 2 and the subsequent conversion of the resulting epoxide with excess CH 3 NH 2 . Quaternization with CH 3 Cl of these mixtures of secondary and tertiary amines yielded exclusively HOPIBOCH 2 O C(OCH 3 )CH 3 OCH 2 ON(CH 3 ) 2 from the secondary amine, whereas the tertiary (centrally functionalized) amine remained unchanged. Tandem mass spectrometry experiments provided unique insight into the precise connectivity of the functional end groups added to the PIB frame.

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The water absorption of crushed concrete aggregates (CCA) has a major influence on concrete workability. In order to determine the water absorption of CCA, a more porous material than natural aggregates, modifications to the standard pycnometer method are proposed as: (1) Water absorption is measured on a combined fraction CCA consisting of fine and coarse aggregates proportioned according to concrete recipe. (2) The CCA is pre-processed to mitigate sedimentation. (3) Saturated surface dry condition of aggregate is assessed by vacuum filtration and ocular technique. Water absorption development is measured at 0 min, 15 min, and 24 h. About 90% of the 24-h water absorption occurs in 15 min, value which is introduced in the concrete recipe; slump flow and compressive strength are determined. The modified pycnometer method shortens test duration, is operator insensitive and gives reliable water absorption result for CCA leading to concrete workability fitting industrial application.