The Effect of UV Light and Xenon Lamp on Anti-Aging Properties of Recycled Milk-Cartons/PE Composite Siding

The colour change and flextural properties of recycled milk-cartons/PE composite siding after tested in UV light accelerated aging champer and xenon lamp accelerated aging champer were studied. It showed that:(1)The ΔE value of samples in UV light champer was higher a little than it in xenon lamp champer after tested in later 1000h, which indicated UV light accelerated aging had more serious damage on material compared with xenon lamp accelerated aging; (2)The MOE of samples reduced 26.24%、39.82%、45.44% respectively after tested in UV light champer for 500h, 1000h, 1500h, with the MOR reducing 18.39%、19.01%、30.65%; while the MOE reduced 11.91%、29.60%、44.94% respectively after tested in xenon lamp champer for 500h, 1000h, 1500h, with the MOR reducing 8.53%、8.21%、26.02%, which showed that the effect on flextrual properties of UV light champer was greater than xenon lamp champer; (3) FTIR analysis showed it appeared carbonyl absorption peak on sample’s surface and methylene content increased a lot, which indicated polymer molecular chains had degraded into samll molecular chains.

Examination of the Matrix Isolation Fourier Transform Infrared Spectra of Organic Compounds: Part VI

Matrix isolation Fourier transform spectral evidence is presented that documents the isolation of rotational isomers in an argon matrix. The spectral evidence is based on the presence of split carbonyl absorption bands in the spectra of selected derivatives of methyl acetate which do not vary in intensity with changes in the matrix-to-eluate ratios. The results compare very favorably with FT-IR data on the identical compounds obtained in the vapor phase. The low temperature of the matrix isolation experiment (10 K) allows for the observance of rotational isomers not seen at the high temperatures of the vapor-phase experiment (500 K). The presence of multiple carbonyl absorption bands dictates that careful attention must be paid to spectral/structure correlations employing MI/FT-IR data.

Examination of the Matrix Isolation Fourier Transform Infrared Spectra of Organic Compounds: Part VII

A series of lactones and lactams have been examined by matrix isolation Fourier transform infrared spectrometry. The values for the carbonyl absorption bands fall between those reported for the same compounds in the vapor phase and solid state. Multiple absorption bands are found in the region of carbonyl absorption for compounds examined under the matrix isolation phase. Ring strain has a dramatic effect on simplifying the complexity of the spectra. Little or no aggregation effects are observed for either the lactones or lactams under accepted operating parameters. The effects of substituents on these systems are comparable to those found in the vapor-phase and solid-state data.

Examination of the Matrix Isolation Fourier Transform Infrared Spectra of Organic Compounds: Part III

Matrix-isolated (MI) Fourier transform infrared spectra (FT-IR) have been collected on a series of esters and ketones. The values for the carbonyl absorption are intermediate between the values for vapor-phase (VP) and solid-state (SS) phases. The spectra reveal a splitting or broadening of the carbonyl absorption in the majority of cases for both compound types. The splitting, on the order of 5 to 10 cm−1, does not appear to be a function of concentration at ≤20 ng on the cryogenic disk. The splitting is also not unequivocally due to steric hindrance about the carbonyl group. Compounds with liner as well as branched substituents display spectra having split carbonyl absorptions. Isolation of molecules within multiple types of matrix sites is advanced as the predominant cause of the splitting phenomenon. Implications and consequences of the observed splitting are discussed.

Examination of the Matrix Isolation Fourier Transform Infrared Spectra of Organic Compounds: Part IV

Matrix-isolated (MI) Fourier transform infrared spectra (FT-IR) have been collected on a series of aldehydes and acids. The values for the carbonyl absorption are intermediate between the higher values for vapor-phase (VP) and lower values for solid-state (SS) phases. Substituent effects on aromatic rings induce shifts in carbonyl absorptions in the same manner as found in VP and SS studies. The magnitude of the shifts is approximately the same for all three phases. The spectra reveal a splitting or broadening of the carbonyl absorption for both aldehydes and acids. The size of the molecule affects the degree of band broadening. In certain cases discrete conformers appear to have been isolated in the matrix.

Examination of the Matrix Isolation Fourier Transform Infrared Spectra of Organic Compounds: Part II

Matrix-isolated (MI) Fourier transform infrared spectra have been collected on a series of aliphatic ketones. The values for the carbonyl absorptions maxima are intermediate between vapor-phase (VP) and solid-state solution (SS) phases. The data reveal a stereochemical influence on the position of the ketone carbonyl absorption when the carbons that are in the alpha position with respect to the carbonyl group contain alkyl snbstituents vs. protons. Steric bulk causes the frequency of the absorption to decrease. The position of the ketone carbonyl absorption was also shown to decrease as the carbonyl group migrated toward the center of a long straight-chain hydrocarbon backbone. Stereochemical influences due to ring strain were also documented. Unsaturation, located in the alpha position with respect to the carbonyl, was shown to reduce the absorption frequency. The trends found in this MI study are comparable to those previously documented from VP and SS studies. In two cases wherein very bulky substituents were located in the alpha position with respect to the carbonyl, a splitting of the carbonyl absorption was observed. Studies are underway to test for a general trend in and to uncover an explanation for this phenomenon.