Preparation of covalently colored polymer latex through miniemulsion polymerization based on a polymerizable dye

Figures & data

Table 1. Typical recipes of the colored latex preparation via miniemulsion polymerization.

Ingredients	Amount/g
BA	5.00
St	5.00
HD	0.40
AHAQ/PHAQ	Variable
SDS	Variable
APS	Variable
H2O	40.0

Figure 1. UV–vis absorption spectra of AHAQ and PHAQ in ethyl acetate.

Figure 2. Diameter of the monomer droplets/latex particles vs. polymerization time.

Figure 3. Monomer conversion vs. polymerization time.

Figure 4. Miniemulsion polymerization rate vs. monomer conversion.

Table 2. Influence of APS amount on the monomer conversion and the particle size and its distribution.^a

Sample	APS/wt%	Total conv./%	/nm	Poly index
I1	0.5	85.5	118.7	0.144
I2	1.0	92.7	96.1	0.0760
I3	1.5	99.6	75.3	0.0529
I4	2.0	100	65.3	0.0513

^a AHAQ amount was 0.2 wt% to St and BA, and SDS concentration was 40 mM based on the aqueous phase.

Table 3. Properties of the colored latex prepared with different amounts of SDS.^a

Run	SDS conc.^b/mM	Total conv./%	/nm	Poly index	Surface tension/mN/m
S1	10	95.5	122.2	0.144	63.7
S2	15	97.7	100.0	0.0384	62.1
S3	20	96.8	95.0	0.0544	60.8
S4	25	99.7	90.8	0.0553	59.6
S5	30	99.4	86.8	0.0584	58.3
S6	35	98.9	82.1	0.0495	56.2
S7/I3	40	99.6	75.3	0.0513	55.6
S8^c	40	99.8	74.9	0.0674	55.4

^a O/W was 20/80 by mass, APS and AHAQ amount were 1.5wt% and 0.2 wt% of St and BA, respectively.

^b Based on the aqueous phase.

^c PHAQ (0.2 wt% of St and BA) was used instead of AHAQ.

Table 4. Properties of the P(St-BA-AHAQ) latexes prepared with different O/W.^a

Sample	O/W/mass ratio	Total conv./%	/nm	Poly index	Surface tension/mN/m
OW1	10/90	99.1	55.9	0.0413	47.4
OW2	15/85	98.6	65.0	0.0346	51.6
OW3(I3, S7)	20/80	99.6	75.3	0.0513	55.6
OW4	25/75	98.2	82.2	0.0666	59.0
OW5	30/70	98.4	91.3	0.0529	60.1

^a APS and AHAQ amount were 1.5 and 0.2 wt% of St and BA, respectively, and SDS concentration was 40 mM based on the aqueous phase.

Table 5. Influence of dye content on the encapsulation efficiency and monomer conversion.^a

Sample	AHAQ/wt%^b	Total conv./%	Encapsulation efficiency/%	Dye conv./%
D1	0.2	99.6	98.7	96.3
D2	0.4	99.4	97.9	95.7
D3	0.6	99.1	98.3	96.1
D4	0.8	99.3	98.5	95.9
D5	1.0	98.9	97.7	95.4

^a APS was 1.5 wt% of St and BA, SDS concentration was 40 mM based on the aqueous phase, and O/W was 20/80 by mass.

^b To the amount of St and BA.

Figure 5. TEM images of (a) P(St-BA-AHAQ) (sample S7) and (b) P(St-BA)/PHAQ (sample S8) latex particles.

Figure 6. UV–vis absorption spectra of (a) AHAQ and P(St-BA-AHAQ), and (b) PHAQ and P(St-BA)/PHAQ using ethyl acetate as solvent.

Figure 7. Percentage of the dye migrated from the latex film into methanol vs. extraction time (samples S7 and S8).

Figure 8. ΔE of the colored latex films (samples S7 and S8) vs. irradiation time.

Scheme 1. Synthesis of AHAQ and PHAQ.