c) fitting of the NMR intensity in dependence of the recycle delays 4

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1 Supporting Information Prediction of NMR magnetization for onflow experiments: According to Albert, the relaxation rate can be expressed under flow conditions as follows: T flow = T + τ (S-) with T as the relaxation time of stop flow and τ = detection volume/flow rate. T data could be obtained by a) fitting the equation -4 t M = Z (t) M 0 exp (S-) T b) taking the zero position of Equation S- given by t T = (S-3) ln c) fitting of the NMR intensity in dependence of the recycle delays 4 t M = Z (t) M 0 exp (S-4) T where M Z (t) is the magnetization in z direction and M 0 is the magnetization of the equilibrium. It is the aim to improve onflow conditions for a quantitative analysis. In case of polymers it was found that T relaxation times in diluted solutions do not depend on the molar mass 5. Therefore, we can measure the T relaxation times of all species in a NMR tube which would represent the stop flow mode. In this case Equation S-4 can be written as: = t M Z (t) M0 exp (S-5) T The combination of Equations S- and S-5 finally leads to the possibility to predict correction coefficients. Under flow conditions, the zero magnetization M 0 is limited by the residence

2 time τ of a nucleus in the detection cell of the flow probe. Since τ might be shorter than 5 T the following expression is valid: M 0 flow < M 0. If no premagnetization volume is taken into account, Equation S-5 will be used to calculate M 0 flow by simply considering the magnetization for the limiting residence time τ: flow τ M 0 = M Z ( τ) = M 0 exp (S-6) T Equation S-6 allows the calculation of the reduced zero magnetization of the flow M flow 0. Since T is measured (either in the NMR tube or in stop flow mode) and M 0 is also derived from this measurement, M flow flow 0 can be directly calculated. Using the calculated M 0 of Equation S-6, Equation S-4 can be expressed for flow conditions by: flow = flow t M Z (t) M0 exp flow (S-7) T and with Equation S- flow flow M Z (t) = M0 exp t + (S-8) T τ Equation S-8 allows the calculation of correction factors for 90 pulses by comparing equations S-5 and S-8.

3 Basics of SEC-RI-UV: Since the SEC is separating polymers according to their hydrodynamic volume, different polymers have different hydrodynamic volumes at the same molar mass. Therefore the calibration curves are different. The hydrodynamic volume V h of a polymer is given by 6 : V h [ η] M = (S-9) where [η] is the intrinsic viscosity of the polymer and M the molar mass. The calibration curve of a polymer in SEC is given by log M vs V e, where V e is the elution volume. Obviously, results based on a single molar mass calibration of one of the comonomers will not provide accurate molar mass information as the calibration will depend on the hydrodynamic radii based on the local composition of the species. Its hydrodynamic radius will depend on the chemistry of the comonomers and their placement (sequence distribution) in the macromolecule. In the case of block-copolymers of the structure A-B (or A-B-A, A-B-C) with sufficient long A and B block segments, the size (hydrodynamic radius) of the block copolymer will behave like the addition of two homopolymers A and B having the same size. There is only one heterocontact A-B where both chains are connected together which can influence the size of the macromolecule. If the comonomer blocks are sufficient long this defect position can be neglected. The molar mass of the block copolymer can be approximated by the molar mass of the respective segments 7. GPC/SEC with two independent concentration detectors (multi-detector method) based on independent and different response factors for the comonomers provides insight into the composition of the copolymer. This method is based on a calculated copolymer calibration curve if the calibration of two homopolymers of the comonomers is available. It allows the calculation of the average chemical composition, the comonomer distribution and the copolymer average molecular weights 7. The over all detector signal of a concentration detector can be described in general as:

4 S i i ( k c + k c ) = D (S-0) where D i is the detector factor, k, the specific response of comonomer and comonomer and c, the concentration of comonomer and comonomer. If the different response factors for the given comonomers of the copolymer are available, the signal intensity of two different detectors (RI and UV) is given by: S RI RI RI RI RI ( k c + k c ) = (S-) and S UV UV UV UV UV ( k c + k c ) = (S-) The weight fraction for comonomer is given by: w c c + c = (S-3) (The weight fraction of comonomer is simply the difference of -w.). Knowing the response factor for the two monomers for two detectors the concentration of each comonomer at each slice of the polymer can be calculated and therefore also the chemical composition in each slice. The calibration curve of a copolymer requires the weighting of the individual homo polymer calibration via the chemical composition distribution. Consequently, the molar mass calibration of a copolymer consisting of comonomers and results into log M Copol = x log M + x log M (S-4) mol mol Due to this, the copolymer calibration curve for each copolymer can be calculated and constructed individually and the true copolymer molar mass can be determined via the chemical composition (see equation S-4) 8.

5 Table S-. Molar masses of the PS and PMMA homopolymer standards. M W of PS M N of PS M P of PS M N of PMMA M W of PMMA M P of PMMA [kg. mol - ] [kg. mol - ] [kg. mol - ] [kg. mol - ] [kg. mol - ] [kg. mol - ] Table S-. Reference materials for determining the response factors of UV and RI detection. Molar masses and response factors of PS and PMMA reference standards used for copolymer analysis. PS [kg. mol - ] PMMA [kg. mol - ] M W M N M P PDI Response factors [mv/mg] UV(54nm) detector RI detector

6 Table S-3. Molar mass data obtained by SEC-NMR and complex copolymer analysis for a PS and PMMA calibration curve PS calibration PMMA calibration Sample/ M N M W M P M N M W M P Method (kg. mol - ) (kg. mol - ) (kg. mol - ) (kg. mol - ) (kg. mol - ) (kg. mol - ) SEC-NMR SEC (RI) SEC-NMR SEC (RI) SEC-NMR SEC (RI) SEC-NMR SEC (RI) SEC-NMR SEC (RI)

7 Figure S-. SEC analysis of M N of PS (M N =50 kg. mol -, M W =5.5 kg. mol - ) in dependence on the injection concentration by UV detection. Figure S-. Inversion recovery experiment with WET suppression (the second WET period is only executed for t > ); H channel: d = relaxation delay, four selective pulses of 0 ms, 80, 90 hard pulses (90 pulse = 7 µs), acquisition time = 0.9 s; 3 C channel: GARP decoupling of THF satellites; Gradient channel: gradient ratio 8:4:: with ms gradient duration and 40 G. cm - for the first gradient.

8 Figure S-3. T of sample 6 (PS-b-PMMA): PS ( meta,para) and PMMA ( rr triad) derived from Equation S-3. Figure S-4. τ values at different flow rates = PS (meta, para), = PMMA(rr triad), solid line = theoretical τ values (calculated by τ = 60 µl/flow rate).

9 a) b) Figure S-5. NMR intensities of aromatic and methyl protons of PS-b-PMMA (sample 6); a) PS(m,p) and b) PMMA(rr) protons in dependence of the flow rates at different recycle delays; 0.49s, 0.69s, 0.99s,.49s, x.49s, 5.49s (using 90 pulse). a) b) Figure S-6. Correction factors derived from Figure S-5 for (a) different flow rates and recycle delays of the meta-para protons and (b) at 0.8 ml. min - for meta, para, ortho, rr triad, mr triad in dependence on recycle delays.

10 Figure S-7. Theoretical coefficients derived from Equation S-8 based on T measurements (solid blue line = calculated for PS (meta, para), dashed blue line = calculated for PS (ortho), solid red line = calculated for PMMA (rr triad), dashed red line = calculated for PMMA (mr triad), = measured PS (meta, para), = measured PS (ortho), = measured PMMA (rr triad), = measured PMMA (mr triad)) Figure S-8. CCDs of sample 6 determined by experimental and theoretical corrections ( experimental corrected aromatics, theoretical corrected aromatics, experimental corrected aliphatics, theoretical corrected aliphatics).

11 Figure S-9. SEC-NMR calibration curves of molar mass versus retention time for PS and PMMA; = PS data points, = PMMA data points, blue line = PS calibration curve fitted with 3 rd order polynomial, red line = PMMA calibration curve fitted with 3 rd order polynomial. Figure S-0. Copolymer molar mass scale of sample and homopolymer calibration curves; = copolymer curve, blue line = PS calibration curve, red line = PMMA calibration curve.

12 Figure S-. Microstructure distribution of the PMMA block of samples (black), (magenta), 3 (green), 4 (blue), 5 (red) versus molar mass; = mol% rr, = mol% mr, solid line = rr chromatogram of PMMA, dashed line = mr chromatogram of PMMA. References () Albert, K. On-line LC-NMR and Related Techniques; John Wiley & Sons Ltd.: Chichester, 00. () Bloch, F.; Hansen, W. W.; Packard, M. Phys. Rev. 946, 70, (3) Abragam, A. Principles of Nuclear Magnetism; Clarendon Press: Oxford, 96. (4) Claridge, T. D. W. High-Resolution NMR Techniques in Organic Chemistry, Pergamon-Elsevier Science Ltd: Oxford, 999. (5) Tabak, F. J. Mol. Liq. 988, 39, 37-5.

13 (6) Striegel, A. M.; Yau, W. W.; Kirkland, J. J.; Bly, D. D. Modern Size-Exclusion Liquid Chromatography: Practice of Gel Permeation and Gel Filtration Chromatography, nd ed.; Wiley: New Jersey, 009. (7) Runyon, J.R.; Barnes, D.E.; Rudel, J.F.; Tung, L.H. J. Appl. Polym. Sci., 969, 3, (8) Kilz, P.; Pasch, H. Coupled LC techniques in molecular characterization; in Encyclopedia of Analytical Chemistry; R.A. Myers (ed.); Wiley: Chichester, 000.