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SEC Polystyrene Calibration Standards

Source: R/data.R
sec_ps_standards.Rd

Polystyrene narrow molecular weight standards for SEC/GPC conventional calibration. A convenient subset of sec_calibration_standards containing only polystyrene standards.

Usage

sec_ps_standards

Format

A tibble with 16 rows and 12 columns:

standard_name

Character. Standard identifier (e.g., "PS-67500")

mp

Numeric. Peak molecular weight in Da

log_mp

Numeric. log10(Mp) for calibration curve fitting

retention_time

Numeric. Peak retention time in minutes

retention_volume

Numeric. Peak retention volume in mL

mn

Numeric. Number-average molecular weight in Da

mw

Numeric. Weight-average molecular weight in Da

dispersity

Numeric. Polydispersity index (Mw/Mn)

mp_uncertainty

Numeric. Relative uncertainty in Mp

k_value

Numeric. Mark-Houwink K constant (0.000141 mL/g)

a_value

Numeric. Mark-Houwink exponent (0.700)

dn_dc

Numeric. Refractive index increment (0.185 mL/g)

Source

Synthetic data based on typical commercial narrow PS standards.

Details

Polystyrene is the most widely used SEC calibration standard due to its:

  • Availability in narrow dispersity grades across wide MW range

  • Well-characterized Mark-Houwink parameters in common solvents

  • Strong UV absorption for dual detection

  • Good solubility and stability

The 16 standards span 162 Da to 3,150,000 Da, covering typical analytical SEC columns. Standards are pre-sorted by descending molecular weight (elution order).

Usage with step_sec_conventional_cal:


library(dplyr)
standards <- sec_ps_standards |>
  select(retention = retention_time, log_mw = log_mp)

recipe(~., data = my_data) |>
  step_sec_conventional_cal(standards = standards, fit_type = "cubic")

See also

sec_calibration_standards for full dataset with PMMA sec_pmma_standards for PMMA standards step_sec_conventional_cal for calibration step

Other sec-data: sec_branched, sec_calibration_standards, sec_copolymer, sec_pmma_standards, sec_protein, sec_raw_multidetector, sec_raw_standards, sec_raw_unknowns, sec_system_suitability, sec_triple_detect

Other sec-calibration: load_sec_calibration(), save_sec_calibration(), sec_calibration_standards, sec_pmma_standards, step_sec_broad_standard(), step_sec_conventional_cal(), step_sec_universal_cal()

Examples

data(sec_ps_standards)

# Quick look at the calibration range
range(sec_ps_standards$mp)
#> [1]     162 3150000
range(sec_ps_standards$retention_time)
#> [1] 11.150 20.787

# Plot calibration curve
if (requireNamespace("ggplot2", quietly = TRUE)) {
  library(ggplot2)
  ggplot(sec_ps_standards, aes(retention_time, log_mp)) +
    geom_point(size = 3) +
    geom_smooth(method = "lm", formula = y ~ poly(x, 3), se = FALSE) +
    labs(
      x = "Retention Time (min)",
      y = expression(log[10](M[p])),
      title = "PS Calibration Curve (Cubic Fit)"
    ) +
    theme_minimal()
}